static void Main(string[] args)
{
    Action<int> firstAction = DoWorkWithOneParameter;
    Action<int, int> secondAction = DoWorkWithTwoParameters;
    Action<int, int, int> thirdAction = DoWorkWithThreeParameters;

    firstAction(1); // Print 1
    secondAction(1, 2); // Print 1-2
    thirdAction(1, 2, 3); //Print 1-2-3
}

public static void DoWorkWithOneParameter(int arg)
{
    Console.WriteLine(arg);
}

public static void DoWorkWithTwoParameters(int arg1, int arg2)
{
    Console.WriteLine(arg1 + "-" + arg2);
}

public static void DoWorkWithThreeParameters(int arg1, int arg2, int arg3)
{
    Console.WriteLine(arg1 + "-" + arg2 + "-" + arg3);
}

static void Main(string[] args)
{
    Action act = () =>
    {
        Console.WriteLine("No Parameter");
    };

    Action<int> actWithOneParameter = (arg1) =>
        {
            Console.WriteLine("Par: " + arg1);
        };

    Action<int, int> actWithTwoParameter = (arg1, arg2) =>
        {
            Console.WriteLine("Par1: " + arg1 + ", Par2: " + arg2);
        };

    act();
    actWithOneParameter(1);
    actWithTwoParameter(1, 2);
}

using System;

namespace pass_function_as_parameter
{
    class Program
    {
        static int functionToPass(int x)
        {
            return x + 10;
        }
        static void function(Func<int, int> functionToPass)
        {
            int i = functionToPass(22);
            Console.WriteLine("i = {0}", i);
        }
        static void Main(string[] args)
        {
            function(functionToPass);
        }
    }
}

using System;

namespace pass_function_as_parameter
{
    class Program
    {
        static void functionToPass2(int x)
        {
            int increment = x + 10;
            Console.WriteLine("increment = {0}",increment);
        }
        static void function2(Action<int> functionToPass2)
        {
            functionToPass2(22);
        }
        static void Main(string[] args)
        {
            function2(functionToPass2);
        }
    }
}

#include<stdio.h>
#include<string.h>

int check_fibonacci(int fibonacci[], int total)
{
    int i, j, result, sum;

    for(i = 0, j = 2; i < total - 2; i++,j++)
    {
        sum = fibonacci[i] + fibonacci[i+1];

        if(fibonacci[j] == sum)
        {
           result = 1;
        }
        else
        {
            result = 0;
        }
    }
    return result;
}


void main()
{

  int total;
  printf("co bao nhieu so : ");
  scanf("%d", &total);
  int fibonacci[total];

  for(int i = 0; i < total; i++)
  {
      printf("fibonacci %d = ", i + 1);
      scanf("%d", &fibonacci[i]);
  }

   if(check_fibonacci(fibonacci, total) == 1)
   {
       printf("\nla day so fibonacci");
   }
   else
   {
      printf("\nkhong phai day so fibonacci");
   }

}

$ gcc -shared libanswer.so answer.c

vector* sum( vector* v, int n ) {
    vector* r = ( vector* )( malloc( sizeof( vector ) ) );
    for( i = 0; i < n; i++ ) {
        r = add( r, v + i );
    }
    
    return r;
}

typedef struct __vector {
    int x;
    int y;
} vector;

vector* add( vector* a, vector* b ) {
    vector* r = ( vector* )( malloc( sizeof( vector ) ) );
    r->x = a->x + b->x;
    r->y = a->y + b->y;
    
    return r;
}

a = a ^ b;
b = a ^ b;
a = a ^ b;

#include<stdio.h>
#include<windows.h>



void ReadWay(int number)
{
SetConsoleOutputCP(65001);
     int ways;
      ways = number/10;

      switch(ways)
      {

        case 1:
            printf("mười ");
            break;
        case 2:
            printf("hai ");
            break;
        case 3:
            printf("ba ");
            break;
        case 4:
            printf("bốn ");
            break;
        case 5:
            printf("năm ");
            break;
        case 6:
            printf("sáu ");
            break;
        case 7:
            printf("bảy ");
            break;
        case 8:
            printf("tám ");
            break;
        case 9:
            printf("chín ");
            break;
      }

      ways = number%10;
      switch(ways)
      {
        case 0:
            ways = number/10;
            if(ways == 1)
            {
                printf("");
            }
            else
            {
               printf("mươi ");
            }

            break;
        case 1:
            ways = number/10;
            if(ways == 1)
            {
                printf("một");
            }
            else
            {
               printf("mươi mốt");
            }

            break;
        case 2:
            ways = number/10;
            if(ways == 1)
            {
                printf("hai");
            }
            else
            {
                printf("mươi hai");
            }

            break;
        case 3:
            ways = number/10;
            if(ways == 1)
            {
                printf("ba");
            }
            else
            {
                printf("mươi ba");
            }

            break;
        case 4:
            ways = number/10;
            if(ways == 1)
            {
                printf("bốn");
            }
            else
            {
                printf("mươi bốn");
            }

            break;
        case 5:
            ways = number/10;
            if(ways == 1)
            {
                printf("lăm");
            }
            else
            {
               printf("mươi lăm");
            }

            break;
        case 6:
            ways = number/10;
            if(ways == 1)
            {
                printf("sáu");
            }
            else
            {
                printf("mươi sáu");
            }

            break;
        case 7:
            ways = number/10;
            if(ways == 1)
            {
                printf("bảy");
            }
            else
            {
                printf("mươi bảy");
            }

            break;
        case 8:
            ways = number/10;
            if(ways == 1)
            {
                printf("tám");
            }
            else
            {
               printf("mươi tám");
            }

            break;
        case 9:
            ways = number/10;
            if(ways == 1)
            {
                printf("chín");
            }
            else
            {
               printf("mươi chín");
            }

            break;
      }
}


void main()
{
  SetConsoleOutputCP(65001);
  float number, save;
  save = number;
 do
{
   //check input data
   do
    {
    printf("nhập số nguyên: ");
    scanf("%f", &number);

    save = number;

        if(number != (int)number)
        {
        printf("lỗi! phải nhập số nguyên\n");
        }

    }while(number != (int)number);

   //end program
     if(number == 0)
    {
        exit(0);
    }

    system("cls");
    printf("%d đọc là: ", (int)save);

    ReadWay(number);

    printf("\n\nnếu muốn dừng chương trình! >>nhập 0<<\n\n");


}while(number != 0);


}

#include<stdio.h>

//sum
void CountTime(int day, int month, int year)
{
     int Dayth;
     printf("%d/%d/%d is: ", day, month, year);

     for(int i = 1; i < month;i++)
     {
         if( i == 1 || i == 3 || i == 5 || i == 7 || i ==  9 || i == 11)
         {
             if(month == 1)
             {
                Dayth = 0;
             }
             else
             {
                Dayth =  Dayth + 31;
             }

         }
         else if(i == 4 || i == 6 ||i == 8 || i == 10 || i == 12)
         {
             Dayth =  Dayth + 30;
         }
         else
         {
             Dayth =  Dayth + 28;
         }
     }

     printf("[%d]th day in year", Dayth + day);

}


void main()
{
  int day, month, year;


  //check input data
do
{
  do
  {
      printf("enter day: ");
      scanf("%d", &day);
      if(day > 31 || day <= 0)
      {
          printf(">>ERROR! day <= 30\n");
      }
  }while(day > 31 || day <= 0);

  do
  {
     printf("enter month: ");
     scanf("%d", &month);
     if(month > 12 || month < 1)
     {
         printf(">>ERROR! month >= 12\n");
     }
  }while(month > 12 || month < 1);

  if(month == 2 && day > 28 || month == 4 && day > 30 ||
       month == 6 && day > 30 || month == 8 && day > 30 ||
       month == 10 && day > 30 || month == 12 && day > 30)
  {
      printf(">>ERROR! day of month\n");
      printf("month [2] : 28 day\n");
      printf("month [4] [6] [8] [10] [12] : 30 day\n");
      printf("month [1] [3] [5] [7] [9] [11] : 31 day\n\n");
  }

}while(month == 2 && day > 28 || month == 4 && day > 30 ||
       month == 6 && day > 30 || month == 8 && day > 30 ||
       month == 10 && day > 30 || month == 12 && day > 30);

  do
  {
     printf("enter year: ");
     scanf("%d", &year);
     if(year < 2000)
     {
         printf(">>ERROR! year >= 2000");
     }
  }while(year < 2000);


  CountTime(day, month, year);
}

#include<stdio.h>



void NextTime(int day, int month, int year)
{
    // count day and month
    day = day + 1;
    printf("Next time: ");
    if(month == 1 || month == 3 || month == 5 || month == 7 || month == 9 || month == 11)
    {

        if(day > 31 && month < 12)
        {
           printf("1/%d/", month + 1);
        }
        else if(day <= 31 && month < 12)
        {
            printf("%d/%d/",day ,month);
        }
    }

    else if(month == 4 || month == 6 || month == 8 || month == 10 || month == 12)
    {
        if(day > 30 && month == 12)
        {
            printf("1/1/");
        }
        else if(day > 30 && month < 12)
        {
            printf("1/%d/", month + 1);
        }
        else if(day <= 30 && month <= 12)
        {
            printf("%d/%d/", day, month);
        }
    }
    else if(month == 2)
    {
        if(day > 28)
        {
        printf("1/3/");
        }
        else if(day <= 28)
        {
            printf("%d/2/", day);
        }
    }


//count year
  if( day > 30 && month == 12)
  {

     printf("%d", year + 1);
  }
  else if(day <= 31 && month < 12 || day > 31 && month < 12 )
  {
    printf("%d", year);
  }
}



void main()
{
  int day, month, year;


  //check input data
do
{
  do
  {
      printf("enter day: ");
      scanf("%d", &day);
      if(day > 31 || day <= 0)
      {
          printf(">>ERROR! day <= 30\n");
      }
  }while(day > 31 || day <= 0);

  do
  {
     printf("enter month: ");
     scanf("%d", &month);
     if(month > 12 || month < 1)
     {
         printf(">>ERROR! month >= 12\n");
     }
  }while(month > 12 || month < 1);

  if(month == 2 && day > 28 || month == 4 && day > 30 ||
       month == 6 && day > 30 || month == 8 && day > 30 ||
       month == 10 && day > 30 || month == 12 && day > 30)
  {
      printf(">>ERROR! day of month\n");
      printf("month [2] : 28 day\n");
      printf("month [4] [6] [8] [10] [12] : 30 day\n");
      printf("month [1] [3] [5] [7] [9] [11] : 31 day\n\n");
  }

}while(month == 2 && day > 28 || month == 4 && day > 30 ||
       month == 6 && day > 30 || month == 8 && day > 30 ||
       month == 10 && day > 30 || month == 12 && day > 30);

  do
  {
     printf("enter year: ");
     scanf("%d", &year);
     if(year < 2000)
     {
         printf(">>ERROR! year >= 2000");
     }
  }while(year < 2000);


  NextTime(day, month, year);
}

#include<stdio.h>



void increasing(float num1, float num2, float num3)
{
    float save = 0;
    printf("increasing: ");
    if(num1  > num2)
    {
        save = num2;
        num2 = num1;
        num1 = save;
    }
    if(num2 > num3)
    {
        save = num3;
        num3 = num2;
        num2 = save;
    }
    if(num1 > num2)
    {
        save = num2;
        num2 = num1;
        num1 = save;
    }
    printf("%.1f %.1f %.1f", num1, num2, num3);

}
void main()
{
  float num1, num2, num3;
    printf("enter number 1: ");
    scanf("%f", &num1);
    printf("enter number 2: ");
    scanf("%f", &num2);
    printf("enter number 3: ");
    scanf("%f", &num3);

  increasing(num1, num2, num3);
}

#include<stdio.h>


//change negative number to positive number
void change(float num1, float num2, float num3)
{
    printf("changed: [%.1f] [%.1f] [%.1f]", num1 * -1, num2 * -1, num3 * -1);
}
void main()
{
  float num1, num2, num3;
  printf("please enter negative numbers\n");
  
  //check input data 
  do 
  {
    printf("enter number 1: ");
    scanf("%f", &num1);
    printf("enter number 2: ");
    scanf("%f", &num2);
    printf("enter number 3: ");
    scanf("%f", &num3);

     if(num1 >= 0 || num2 >= 0 || num3 >= 0)
     {
      printf("please enter negative numbers\n");
     }
  }while(num1 >= 0);

  change(num1, num2, num3);
}

#include<stdio.h>

void main()
{
  int n, sum;
  int count = 0;
    printf("enter n: ");
    scanf("%d", &n);

    for(int i = 1; i < n;i++)
    {
      sum = sum + i;
       if(sum >= n)
       {
           break;
       }
       count = count + 1;
    }

    printf("count = %d", count);
}

#include<stdio.h>

void main()
{
  int n, sum;
    printf("enter n: ");
    scanf("%d", &n);

    for(int i = 1; i < n;i++)
    {
       if(i % 2 == 0)
       {
           continue;
       }
       sum = sum + i;
    }

    printf("sum of odd numbers = %d", sum);
}

#include<stdio.h>

void main()
{
    for(int i = 65; i <= 90;i++)
    {
       printf("%c, ", i);
    }
}

#include<stdio.h>



int FindX(int n)
{
    int sum, count;
    for(int j = 1; sum <= n;j++)
  {
    sum = sum + j;
        if(sum > n)
        {
        break;
        }
    count = count + 1;
  }
  return count;
}
void main()
{
int n;
    printf("enter n: ");
  do
   {
     scanf("%d", &n);
     if(n < 0)
       {
         printf("n must greater than 0")
       }
   }while(n < 0)
    
    printf("X = %d", FindX(n));
    getch();
}

#include<stdio.h>
#include<string.h>
#include<windows.h>

//check duplicate ID
int check_ID(int ID[], int i)
{
 int result;

 for(int j = 0; j < i; j++)
 {
    if(ID[i] == ID[j])
    {
      result = 1;
    }
 }
   return result;
}

//input student information
void InputStudentInfor(int ID[], float grade[], int total)
{

 int i, j, check_input ;
 char temp;

 for(i = 0; i < total; i++)
 {
    do
    {
       printf("\n--> Student %d | ID: ", i+1);
       fflush(stdin);
       check_input = scanf("%d%c", &ID[i], &temp);//check_input will check how many values are scanned

       if(check_input == 2 && temp != '\n' || check_input == 0)
       {
         printf("\n--- ERROR! can't enter character\n");
       }
       else if(ID[i] < 0)
       {
         printf("\n--- ERROR! please, enter positive number\n");
       }
       else if(check_ID(ID, i)== 1)
       {
         printf("\n--- Student ID already exists\n");
       }
       else
       {
         break;
       }

    }while(check_input == 2 && temp != '\n' || check_input == 0 || ID[i] < 0 || check_ID(ID, i)== 1);


    do
    {
       printf("\n--> Grade %d : ", i+1);//check_input will check how many values are scanned
       fflush(stdin);
       check_input = scanf("%f%c", &grade[i], &temp);

       if(check_input == 2 && temp != '\n' || check_input == 0 )
       {
         printf("\n--- ERROR! can't enter character\n");
       }
       else if(grade[i] < 0 || grade[i] > 10)
       {
         printf("\n--- ERROR! please, enter number from 1 to 10\n");
       }
       else
       {
         break;
       }

    }while(check_input == 2 && temp != '\n' || check_input == 0 || grade[i] < 0 || grade[i] > 10);
 }
}

//


// Output information of student entered
void OutputStudentInfor(int ID[],float grade[], int total)
{
 for(int i = 0; i < total; i++)
 {
    printf("|%d Student ID: [%d] | Grade: %.2f |\n",i+1 ,ID[i], grade[i]);
 }
}

// Find maximum grade
float FindMaxGrade(float grade[], int total)
{
 float max = grade[0];
 for(int i = 1; i < total;i++ )
 {
    if( max < grade[i])
    {
      max = grade[i];
    }
 }
    return max;
}

//Fin minimum grade
float FindMinGrade(float grade[], int total)
{
 float min = grade[0];
 for(int i = 1; i < total;i++ )
 {
    if( min > grade[i])
    {
      min = grade[i];
    }
 }
    return min;
}

void main()
{
 int total, choice, check_input;
 char temp;
 system("color 0A");//change the color of all characters to green in the console window

   // enter the number of elements of the array and check input data
 do
 {
   printf("--> Enter total number of  student: ");
   fflush(stdin);
   check_input = scanf("%d%c", &total, &temp);//check_input will check how many values are scanned

   if(check_input == 2 && temp != '\n' || check_input  == 0)
   {
     printf("\n--- ERROR! can't enter character<<\n\n");
   }
   else if(total <= 0)
   {
     printf("\n--- ERROR! please, enter value must be greater than 0\n\n");
   }
   else
   {
     break;
   }

 }while(total <= 0 || check_input == 2 && temp !='\n' || check_input == 0);

 system("cls");

 int ID[total];
 float grade[total];

 printf(">>> Enter student ID and grade\n");

 InputStudentInfor(ID, grade, total);
 system("cls");
 printf(">>> Finished entering data");
   //menu initialization
 do
 {

    printf("\n\n\n\t\tMENU");
    printf("\n****************************************\n");
    printf("* 1. Re-enter data                     *\n");
    printf("* 2. print ID and grade of student     *\n");
    printf("* 3. Find maximum grade                *\n");
    printf("* 4. Find minimum grade                *\n");
    printf("* 5. Exit                              *\n");
    printf("****************************************\n\n");

 //check input data
    do
    {
        printf("--> Enter choice: ");
        fflush(stdin);
        check_input = scanf("%d%c", &choice, &temp);//check_input will check how many values are scanned

        if(check_input == 2 && temp != '\n' || check_input  == 0)
        {
            printf("\n--- ERROR! can't enter character<<\n\n");
        }
        else if(choice > 5 || choice < 1)
        {
            printf("\n--- ERROR! please choose from 1 to 5\n\n");
        }
        else
        {
            break;
        }

    }while(check_input == 2 && temp != '\n' || check_input  == 0 ||  choice > 5 || choice < 1);

    system("cls"); //delete screen

    //function selection
    switch(choice)
    {
        case 1:
            system("cls");
            printf(">>> Re-enter data\n\n");

            InputStudentInfor(ID, grade, total);

            printf(">>> Finished entering data");
            system("cls");
            break;

        case 2:
            system("cls");
            printf(">>> List ID and grade of student\n\n\n");

            OutputStudentInfor(ID, grade, total);
            break;

        case 3:
            system("cls");
            printf(">>> Maximum grade: %.2f \n", FindMaxGrade(grade, total));
            break;

        case 4:
            system("cls");
            printf(">>> Minimum grade: %.2f \n", FindMinGrade(grade, total));
             break;

        default :
            printf("\n>>> Program has ended!\n");
            exit(0);
    }

 }while(choice <= 4);
}

uint64_t rdtsc() {
  uint32_t hi, lo;
  __asm__ __volatile__ ("rdtsc" : "=a"(lo), "=d"(hi));
 
  return ( (uint64_t)lo)|( ((uint64_t)hi)<<32 );
 }

#include "sodium.h"

int foo() {
  char myString[32];
  uint32_t myInt;
  if (sodium_init() < 0) return 1;
  randombytes_buf(myString, 32);
  myInt = randombytes_uniform(10);
}

int fd = open("/dev/urandom", O_RDONLY);
if (fd == -1)
	goto nodevurandom
if (fstat(fd, &st) == -1 || !S_ISCHR(st.st_mode)) {
	close(fd);
	goto nodevrandom;
}
if (ioctl(fd, RNDGETENTCNT, &cnt) == -1) {
	close(fd);
	goto nodevrandom;
}
ssize_t ret = read(fd, (char *)buf + i, wanted);
if (ret == -1) {
	if (errno == EAGAIN || errno == EINTR)
		continue;
		close(fd);
		goto nodevrandom;
}
close(fd);
if (gotdata(buf, len) == 0) {
	errno = save_errno;
	return 0;
}
nodevrandom:
	errno = EIO;
	return -1;

int sum_num(int num[], int total)
{
    int sum;
    for(int i = 0; i < total;i++)
    {
        sum = sum +  num[i];
    }
    return sum;
}
int findmax(int num[], int total)
{
    int max;
    max = num[0];
    for(int i = 1; i < total;i++)
    {
        if(max < num[i])
            {
                max = num[i];
            }
    }
    return max;
}
int findmin(int num[], int total)
{
    int min;
    min = num[0];
    for(int i = 1; i < total;i++)
    {
        if(min > num[i])
            {
                min = num[i];
            }
    }
    return min;
}
void main()
{
   int sum, max, min, total;
    printf("enter total: ");
    scanf("%d", &total);
   int num[total];
   for(int i = 0;i < total;i++)
   {
      printf("num %d : ",i+1);
      scanf("%d", &num[i]);
   }

   sum = sum_num(num, total);
   max = findmax(num, total);
   min = findmin(num, total);
   printf("sum = %d\n", sum);
   printf("max = %d\nmin = %d", max, min);
}

#include<stdio.h>



int findexpon(int number, int index)
{
    int expon = 1;
    for(int i = 1; i <= index; i++)
    {
        expon = expon  * number;
    }

    return expon;
}

int finfact(int number)
{
    int sum;
    int fact = 1;
    for(int i = 1; i <= number; i++)
    {
        fact = fact * i ;
    }
    return fact;
}

void main()
{
    int number, fact, index, expon;
    printf("enter value :  ");
    scanf("%d", &number);
    printf("enter exponential: ");
    scanf("%d", &index);

    expon = findexpon(number, index);
    fact = finfact(number);
    
    if(index > 0)
      {
        printf("%d! = %d\n",number, fact);
        printf("%d^%d = %d", number, index, expon);
      }
    else
      {
        printf("enter exponential > 0")
      }


}

#include<stdio.h>
#include<stdbool.h>
#include<conio.h>
#include<math.h>
#include<string.h>

void main()
{
    float s, r, p;
    float area(float r);
    float perimeter(float r);
    printf("enter radius: ");
    scanf("%f", &r);
    s = area(r);
    p = perimeter(r);
    printf("area of circle is %f", s);
    printf("\nPerimeter of circle is %f", p);


}

float area(float r)
{
    float s;
    s = 3.14 * r * r;
    return s;
}

float perimeter(float r)
{
    float p = 2 * 3.14 * r;
    return p;

}

#include<stdio.h>
#include<stdbool.h>
#include<conio.h>
#include<math.h>
#include<string.h>

void main()
{
   int num1, num2, sum;
   char math;
   printf("Enter num 1: ");
   scanf("%d", &num1);
   printf("enter num 2: ");
   scanf("%d", &num2);
   fflush(stdin);
   printf("Enter calculation : ");
   scanf("%C", &math);
   switch(math)
   {
       case '+':
       sum = add(num1, num2);
       printf("%d + %d = %d",num1 ,num2, sum);
       break;
       case '-':
       sum = sub(num1, num2);
       printf("%d - %d = %d",num1 ,num2, sum);
   }




}

int add(int a, int b)
{
     int sum;
     sum = a + b;
    return sum;
}

int sub(int a, int b)
{
    int sum;
    a - b;
    return sum;
}

#include<stdio.h>

void main()
{
int month;
    printf("enter month: ");
    do
    {
       scanf("%d", &month);
       if(month <= 0 || month > 12)
       {
           printf("enter month from 1 to 12\n");
           printf("enter month: ");
       }
    }while(month <= 0 || month > 12);

  if(month == 1 || month == 2 || month == 3 )
  {
     printf("%d month is the 1st quarter", month);
  }
  else if(month == 4 || month == 5 || month == 6)
  {
     printf("%d month is the sendcon quarter", month);
  }
  else if(month == 7 || month == 8 || month == 9)
  {
     printf("%d month is the third quarter", month);
  }
  else
  {
     printf("%d month is the fourth quarter", month);
  }
}

#include<stdio.h>
#include<stdbool.h>
#include<conio.h>
#include<math.h>
#include<string.h>
//đếm số lượng chữ số của số nguyên dương
void main()
{
   int n;
   int i;
   int count = 0;
   printf("enter number: ");
   scanf("%d", &n);

   for(i = 1; i <= n; i++)
   {
    count++;
    n = n/10;
   }
    printf("entered number has %d digits", count+1);
    getch();
}

#include<stdio.h>
#include<stdbool.h>
#include<conio.h>
#include<math.h>
#include<string.h>

void main()
{
   int number;  
   int i, surplus, sum; 

   printf("enter number: "); // nhập số cần đảo ngược
   scanf("%d", &num);
   printf("how many digits in the entered number : ");
   scanf("%d", &sum);

   printf("reversed number of %d is ", num);
   for (i = 1; i <= sum;i++)
   {
       surplus = num%10;   // tìm số dư của số đã cho và in lần lượt sẽ được số đảo ngược
       printf("%d", surplus);
       num = num/10;
   }
  
    getch();
}

#include<stdio.h>
#include<stdbool.h>
#include<conio.h>
#include<math.h>
#include<string.h>

void main()
{
   int temp, i, j;
   temp = 0;
   char chars[20];

    printf("enter chars : ");
    gets(chars);

    if(chars[0] != 'G')
    {
        temp = 1;

    }
    else if (chars[1] != 'C')
    {
        temp = 1;

    }
    else
    {
        for (i = 2; i < strlen(chars);i++)
        {

            if(isdigit(chars[i]) == 0)
                {
                    temp = 1;
                }
                break;
        }
    }

     if ( temp == 0)
     {
         printf("student ID: ");
         puts(chars);
     }
     else
     {
        printf("enter error");
     }

    getch();

}

#include<stdio.h>
#include<stdbool.h>
#include<conio.h>
#include<math.h>
#include<string.h>

void main()
{
   int temp, i, j;
   temp = 0;
   char chars[20];

    printf("enter chars : ");
    gets(chars);

    for(i = 0, j = strlen(chars)-1; i < j; i++, j--)
    {
        if(chars[i] != chars[j])
        {
            temp = 1;
            break;
        }
    }

     if ( temp == 0)
     {
         printf("symmetric chain");
     }
     else
     {
        printf("not symmetric chain");
     }

    getch();

}

#include<stdio.h>
#include<stdbool.h>
#include<conio.h>
#include<math.h>
#include<string.h>

void main()
{
   int result;
   char studentID[20];

   printf("enter ID length  must is 7 characters: ");
A:
   gets(studentID);

   result = strlen(studentID);

   if(result == 7)
   {
       printf("true");
   }
   else
   {
       printf("ID length  must is 7 characters\n");
       printf("re-enter : ");
       goto A;
   }

    getch();

}

#include<stdio.h>
#include<stdbool.h>
#include<conio.h>
#include<math.h>
#include<string.h>

void main()
{
   int choice;
   int choose;
   char str1[20], str2[20];

   printf("enter string 1: ");
   gets(str1);
   printf("enter string 2: ");
   gets(str2);


  do
  {
   printf("\n");
   printf("==========================\n");
   printf("= 1. compare two strings =\n");
   printf("= 2. copy string         =\n");
   printf("= 3. concatenation       =\n");
   printf("= 4. exit                =\n");
   printf("==========================\n");

   printf("choice: ");
   scanf("%d", &choice);
   int result;

   switch(choice)
   {
   case 1:
    result = strcmp(str1, str2);
    if(result == 0)
    {
        printf("two strings is equal");
    }
    if (result > 0)
    {
       printf("string 1 > string 2");
    }
    else
    {
        printf("string 1 < string 2");
    }
    break;
   case 2:
       printf("you wants copy string 1 into 2(input: 1)or 2 into 1(input 2) ?\n");
       printf("choose: ");
       scanf("%d", &choose);
        if(choose == 2)
        {
            strcpy(str1, str2);
            printf("string 2: ");
            puts(str2);
            printf("string 1: ");
            puts(str1);

        }
        else
        {
            strcpy(str2, str1);
            printf("string 2: ");
            puts(str2);
            printf("string 1: ");
            puts(str1);
        }
        break;
   case 3:
        printf("you wants concatenation string 1 into 2(input: 1)or 2 into 1(input 2) ?\n");
        printf("choose: ");
         scanf("%d", &choose);
        if(choose == 2)
        {
            strcat(str1, str2);
            printf("string 1:");
            puts(str1);
        }
        else
        {
            strcat(str2, str1);
            printf ("string 2: ");
            puts(str2);

        }
    break;
   default :
       exit(0);
    break;
   }

  }while( choice <= 3);






    getch();

}

#include<stdio.h>
#include<stdbool.h>
#include<conio.h>
#include<math.h>
#include<string.h>

void main()
{
   char str[5][20];
   int i;

   for (i = 0; i < 5; i++)
   {
     printf("enter string %d: ", i+1);
     gets(str[i]);
   }

   for(i = 0;i<5;i++)
   {
      printf("string entered %: ", i+1);
      puts(str[i]);
   }


    getch();

}

#include<stdio.h>
#include<math.h>
#include<stdbool.h>
void main()
{
    int a[20];
    int j, i, k, h, save;

    i = -1;

    do
    {
        i++;
        printf("enter value a  %d = ", i + 1);
        scanf("%d", &a[i]);
    }while(a[i] >= 0);

    for (k = 0; k < i - 1; k++)
    {
        for (h =k + 1; h < i; h++)
        {
             if(a[k]>a[h])
             {
                save = a[k];
                a[k] = a[h];
                a[h] = save;
             }
        }
    }

   printf("a = ");
   for ( j = 0; j < i; j++ )
      printf("%d\t", a[j]);

  getch();
}

#include<stdio.h>
#include<math.h>
#include<stdbool.h>
void main()
{
    int A[20] ;
    int B[20];
    int i, j, n;

    printf("enter value n : ");
    scanf("%d", &n);


    for( i = 0; i < n; i++)
    {
        printf("A %d = ", i + 1);
        scanf("%d", &A[i]);



    }


        for (i = n-1, j = 0; i >= 0;i--, j++)
    {
        B[j] = A[i];

    }

    printf("B = ");
    for (j = 0; j < n;j++)
    {
        printf(" %d", B[j]);
    }


  getch();
}

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
 
#define MY_TMP_FILE "/tmp/file.tmp"
 
 
int main(int argc, char* argv[])
{
    FILE * f;
    if (!access(MY_TMP_FILE, F_OK)) {
        printf external link("File exists!\n");
        return EXIT_FAILURE;
    }
    tmpFile = fopen(MY_TMP_FILE, "w");
 
    if (tmpFile == NULL) {
        return EXIT_FAILURE;
    }
 
    fputs("Some text...\n", tmpFile);
 
    fclose(tmpFile);
 
    return EXIT_SUCCESS;
}

#include <stdio.h>
int main () {
    char username[8];
    int allow = 0;
    printf external link("Enter your username, please: ");
    gets(username);
    if (grantAccess(username)) {
        allow = 1;
    }
    if (allow != 0) {
        privilegedAction();
    }
    return 0;
}

#define R(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
void salsa20_word_specification(uint32 out[16],uint32 in[16])
{
    int i;
    uint32 x[16];
    for (i = 0;i < 16;++i) x[i] = in[i];
    for (i = 20;i > 0;i -= 2) {
        x[ 4] ^= R(x[ 0]+x[12], 7);  x[ 8] ^= R(x[ 4]+x[ 0], 9);
        x[12] ^= R(x[ 8]+x[ 4],13);  x[ 0] ^= R(x[12]+x[ 8],18);
        x[ 9] ^= R(x[ 5]+x[ 1], 7);  x[13] ^= R(x[ 9]+x[ 5], 9);
        x[ 1] ^= R(x[13]+x[ 9],13);  x[ 5] ^= R(x[ 1]+x[13],18);
        x[14] ^= R(x[10]+x[ 6], 7);  x[ 2] ^= R(x[14]+x[10], 9);
        x[ 6] ^= R(x[ 2]+x[14],13);  x[10] ^= R(x[ 6]+x[ 2],18);
        x[ 3] ^= R(x[15]+x[11], 7);  x[ 7] ^= R(x[ 3]+x[15], 9);
        x[11] ^= R(x[ 7]+x[ 3],13);  x[15] ^= R(x[11]+x[ 7],18);
        x[ 1] ^= R(x[ 0]+x[ 3], 7);  x[ 2] ^= R(x[ 1]+x[ 0], 9);
        x[ 3] ^= R(x[ 2]+x[ 1],13);  x[ 0] ^= R(x[ 3]+x[ 2],18);
        x[ 6] ^= R(x[ 5]+x[ 4], 7);  x[ 7] ^= R(x[ 6]+x[ 5], 9);
        x[ 4] ^= R(x[ 7]+x[ 6],13);  x[ 5] ^= R(x[ 4]+x[ 7],18);
        x[11] ^= R(x[10]+x[ 9], 7);  x[ 8] ^= R(x[11]+x[10], 9);
        x[ 9] ^= R(x[ 8]+x[11],13);  x[10] ^= R(x[ 9]+x[ 8],18);
        x[12] ^= R(x[15]+x[14], 7);  x[13] ^= R(x[12]+x[15], 9);
        x[14] ^= R(x[13]+x[12],13);  x[15] ^= R(x[14]+x[13],18);
    }
    for (i = 0;i < 16;++i) out[i] = x[i] + in[i];
}

i = 0
j = 0
for b in range(m):
    i = (i + 1) % 256
    j = (j + S[i]) % 256
    S[i], S[j] = S[j], S[i]
    KS[b] = S[(S[i] + S[j]) % 256]

j = 0;
S = range(256)
for i in range(256):
    j = (j + S[i] + K[i%n]) % 256
    S[i], S[j] = S[j], S[i]

#include <stdio.h>
int main()
{
	int lenght,bredth;
	int end;
	printf("what is the lenght of the rectangle \n");
	scanf("%d",&lenght);
	printf("what is the bredth of rectangle \n");
    scanf("%d",&bredth);
    printf("area of rectangle = %d \n",lenght*bredth);
    printf("Programe By Aaryan \n");
    printf("press any key to proseed");
    scanf("%d",&end);
	return 0;
} 

#include<stdio.h>
#define take(n) scanf("%d",&n);
#define rep(i,a,b) for(int i=a;i<b;i++)
void add_10(int n){
    printf("Enter a number\n");
    int x;
    take(x);
    printf("%d+%d=%d\n",n,x,n+x);
}
void multiply_10(int n){
    printf("Enter a number\n");
    int x;
    take(x);
    printf("%d*%d=%d\n",n,x,n*x);
}

int main()
{
    int n=10;
    char choice;
    int flag=0;
    do{
        printf("Enter your choice either a or b, any other to exit\n");
        scanf("%c",&choice);
        switch(choice){
            case 'A':
            case 'a': add_10(n);
            break;
            case 'B':
            case 'b': multiply_10(n);
            break;
            default: flag=1;
        }
    }while(flag==0);
return 0;
}

#include<stdio.h>
typedef struct student{
    int roll;
    char name[100];
    int marks[3];
}st;
void takeinput(st candidate[]){
     for(int i=0;i<5;i++){
        printf("\nFor student %d\n",i+1);
        printf("Enter the following details\n");
        printf("roll:");
        scanf("%d",&candidate[i].roll);
        printf("name:");
        scanf("%s",candidate[i].name);
        for(int j=0;j<3;j++){
            printf("marks in subject %d:",j+1);
            scanf("%d",&candidate[i].marks[j]);
        }
     }
}
void printinput(st candidate[]){
    printf("The details of all the students are as follows\n");
    for(int i=0;i<5;i++){
        printf("\nroll no:%d\nname:%s\n",candidate[i].roll,candidate[i].name);
        for(int j=0;j<3;j++){
            printf("marks in subject %d:%d\n",j+1,candidate[i].marks[j]);
        }
    }
}
void average_st_mks(st candidate[]){
    printf("Enter the serial number(1-5) of the student whose average marks to be known\n");
    int no;
    scanf("%d",&no);
    int sum=0;
    for(int i=0;i<3;i++) sum+=candidate[no-1].marks[i];
    float avg=(float)sum/3;
    printf("The average marks candidate bearing roll:%d is %.2f\n",candidate[no-1].roll,avg);
}
void average_subj_mks(st candidates[]){
    printf("Enter the serial number(1-3) of the subject whose average is to be known\n");
    int subject_number;
    scanf("%d",&subject_number);
    int sum=0;
    for(int i=0;i<5;i++){
        sum+=candidates[i].marks[subject_number-1];
    }
    float avg=(float)sum/5;
    printf("The average score of students in subject no:%d is %.2f\n",subject_number,avg);
}
void swap(st *candidate){
    printf("Enter the serial number(1-5) of student whose subject marks are to be swapped\n");
    int i;
    scanf("%d",&i);
    printf("Enter the serial number(1-3) of two subjects whose marks to be swapped\n");
    int a,b;
    scanf("%d%d",&a,&b);
    int temp=candidate[i-1].marks[a-1];
    candidate[i-1].marks[a-1]=candidate[i-1].marks[b-1];
    candidate[i-1].marks[b-1]=temp;
}
void print_mks_student(st candidate[]){
    printf("Enter the serial number(1-5) of the student you want to print marks\n");
    int n;
    scanf("%d",&n);
    for(int i=0;i<3;i++){
        printf("subject %d: %d mks\n",i+1,candidate[n-1].marks[i]);
    }
}
void upp_to_low(st candidate[]){
    printf("Enter the serial number(1-5) of student you want to convert name to lowercase\n");
    int n;
    scanf("%d",&n);
    int i=0;
    do{
        char ch=candidate[n-1].name[i];
        if(ch>=65 && ch<=90) candidate[n-1].name[i]=ch+32;
        i++;
    }while(candidate[n-1].name[i]!='\0');
    printf("student name changed to %s\n",candidate[n-1].name);
}
int main(){
    st candidate[5];
    int flag=1;
    char choice;
    do{
        printf("\nEnter the choice from the menu as per mentioned in the question paper\n");
        printf("The choice should be between a-g(lowercase)\nEnter any other character to stop the program\n");
        scanf(" %c",&choice);
        switch(choice){
        case 'a':takeinput(candidate);
        break;
        case 'b':printinput(candidate); 
        break;
        case 'c':average_st_mks(candidate);
        break;
        case 'd':average_subj_mks(candidate);
        break;
        case 'e':swap(candidate);
        break;
        case 'f':print_mks_student(candidate);
        break;
        case 'g':upp_to_low(candidate);
        break;
        default: flag=0;
        }
    }while(flag==1);
    return 0;
}

class int_ptr_wrapper
{
public:
    int_ptr_wrapper(int value = 0) :
    mInt(new int(value))
    {}

    // note! needs copy-constructor and copy-assignment operator!

    ~int_ptr_wrapper()
    {
        delete mInt;
    }

private:
    int* mInt;
};

class Wrapper
{
 private:
  CLib *lib;

 public:
  Wrapper() { lib = lib_init(); } // Lib initialisieren
  ~Wrapper() { lib_cleanup(&init); } // Lib freigeben

  std::string DoSomething() 
  { 
    char *cstr = lib_get_str(); // String anfordern (malloc!)

    std::string s = str;  // in std::string kopieren

    lib_free_str(cstr); // String freigeben (free)

    return s; // std::string zurückgeben. Alles easy.
  }
};

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <float.h>

//1.
double opA(int, int,int);
double opB(int,int,int);
double opC(int,int,int);
double opD(int,int,int);

int main() {
	int x = 0, y = 0, z = 0;
	char op = '\0';
	double rez = 0.0;

	printf("Unesi tri broja:\t");
	scanf(" %d %d %d", &x, &y, &z);


	printf("Unesi slovo operacije:\t");
	scanf(" %c", &op);

	switch (op) {
	case 'a':
		rez = opA(x, y, z);
		break;
	case 'b':
		rez = opB(x, y, z);
		break;
	case 'c':
		rez = opC(x, y, z);
		break;
	case 'd':
		rez = opD(x, y, z);
		break;

	default:
		printf("Kriva operacija!\n");
		rez = -DBL_MAX;
	}
	if (rez != -DBL_MAX) {
		printf("Rezultat je %lf.\n", rez);

	}
}

double opA(int x, int y, int z) {
	return x+y+z;
}

double opB(int x, int y, int z) {
	return x * y * z;
}
double opC(int x, int y, int z) {
	if (y == 0) {
		return -DBL_MAX;
	}
	return (x / y) + z;
}
double opD(int x, int y, int z) {
	double temp = 0.0;
	if (y == 0) {
		printf("Y ne smije bit 0!\n");
		return -DBL_MAX;
	}
	temp=(x / y - z);
	if (temp < 0) {
		printf("Sadrzaj u korijenu ne smije bit manji od 0!\n");
		return -DBL_MAX;
	}
	return sqrt(temp);
}

//2.
int X = 0;
void funkcija(int);
int main() {
	int Y = 0;
	
	printf("Unesi X i Y!\n");
	scanf(" %d %d", &X, &Y);
	funkcija(Y);
	return 0;
}
void funkcija(int par) {
	printf("X = %d\t Y = %d\t", X, par);
}
//3.
int dohvatiFaktorijelu(int);

int main() {
	int x = 0;
	int fact = 0;
	
	printf("Unesi x!\n");
	scanf(" %d", &x);

	fact=dohvatiFaktorijelu(x);
	printf("Faktorijela broja %d je %lf.\n", x, fact);
	return 0;
}
int dohvatiFaktorijelu(int x) {
	double rez = 1;
	int i = 1;

	for (i = 2; i <= x; i++) {
		rez *= i;
	}
	return rez;
}
//4.
double dohvatiEuler(int, int);
double dohvatiFaktorijelu(int);

int main() {
	int numOfRep = 10;
	int x = 0;
	double euler = 0;
	
	printf("Unesi x:\t");
	scanf(" %d", &x);

	euler=dohvatiEuler(x, 5);
	printf("e(%d) = %lf\n", x, euler);

	euler = dohvatiEuler(x, 10);
	printf("e(%d) = %lf\n", x, euler);

	euler = dohvatiEuler(x, 50);
	printf("e(%d) = %lf\n", x, euler);

	printf("exp(%d) = %lf\n", x, exp(x));
	return 0;
}
double dohvatiEuler(int x, int numOfRep) {
	double rez = 0;
	int i = 0;

	for (i = 0; i <= numOfRep; i++) {
		rez += pow(x,i)/dohvatiFaktorijelu(i);
	}
	return rez;
}
double dohvatiFaktorijelu(int n) {
	int i = 0;
	double rez = 1;

	for (i = 2; i <= n; i++) {
		rez *= i;
	}
	return rez;
}

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <conio.h>
#include <ctype.h>
#define MAT_SIZE 3
#define NAME_LEN 129
#define ARR_LEN 5

//1.
int main() {
	int A[MAT_SIZE][MAT_SIZE] = { 0 };
	int B[MAT_SIZE][MAT_SIZE] = { 0 };
	int i = 0, j = 0;

	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%dx%d:\t", i + 1, j + 1);
			scanf(" %d", &A[i][j]);
		}
	}

	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			B[i][j] = 5 * A[i][j];
		}
	}

	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%d ", B[i][j]);
		}
	}
	printf("\n");
}

//2.
int main() {
	int A[MAT_SIZE][MAT_SIZE] = { 0 };
	int B[MAT_SIZE][MAT_SIZE] = { 0 };
	int i = 0, j = 0;

	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%dx%d:\t", i + 1, j + 1);
			scanf(" %d", &A[i][j]);
		}
	}

	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			B[i][j] = 5 * A[j][i];
		}
	}

	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%d ", B[i][j]);
		}
	}
	printf("\n");
}
//3.
int main() {
	int A[MAT_SIZE][MAT_SIZE] = { 0 };
	int B[MAT_SIZE][MAT_SIZE] = { 0 };
	int C[MAT_SIZE][MAT_SIZE] = { 0 };
	int D[MAT_SIZE][MAT_SIZE] = { 0 };

	int i = 0, j = 0, temp = 0, x = 0;

	printf("Matrica A:\n");
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%dx%d:\t", i + 1, j + 1);
			scanf(" %d", &A[i][j]);
		}
	}
	printf("Matrica B:\n");
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%dx%d:\t", i + 1, j + 1);
			scanf(" %d", &B[i][j]);
		}
	}
	printf("Matrica C:\n");
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%d ", C[i][j]);
		}
	}
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			temp = 0;
			for (x = 0; x < MAT_SIZE; x++) {
				temp += (A[i][x] * B[x][j]);
			}
			D[i][j] = temp;
		}
	}

	printf("Matrica D:\n");
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%d ", D[i][j]);
		}
	}
	printf("\n");
}
//4.
int main() {
	char names[ARR_LEN][NAME_LEN] = { "\0" };
	int i = 0, j = 0, temp = 0, firstIndex = 0, lastIndex = 0;
	char first[NAME_LEN] = { "\0" };
	char last[NAME_LEN] = { "\0" };

	for (i = 0; i < ARR_LEN; i++) {
		printf("Unesi ime osobe broj %d:\t", i + 1);
		scanf(" %s", names[i]);
	}

	firstIndex = 0;
	strcpy(first, names[0]);
	for (i = 1; i < ARR_LEN; i++) {
		if (_strcmpi(first, names[i]) > 0) {
			firstIndex = i;
			strcpy(first, names[i]);
		}
	}
	lastIndex = 0;
	strcpy(last, names[0]);
	for (i = 1; i < ARR_LEN; i++) {
		if (_strcmpi(last, names[i]) < 0) {
			lastIndex = i;
			strcpy(last, names[i]);
		}
	}
	printf("Prva osoba po abecedi je na indexu %d, ime je %s.\n", firstIndex, first);
	printf("Zadnja osoba po abecedi je na indexu %d, ime je %s.\n", lastIndex, last);
	
	for (i = 0; i < ARR_LEN - 1; i++) {
		for (j = i + 1; j < ARR_LEN; j++) {
			if (_strcmpi(names[i], names[j]) > 0) {
				strcpy(temp, names[i]);
				strcpy(names[i], names[j]);
				strcpy(names[j], temp);
			}
		}
	}
	printf("Sortirana imena:\n");
	for (i = 0; i < ARR_LEN; i++) {
		printf("%s\n", names[i]);
	}
}

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <conio.h>
#include <ctype.h>
#define STR_LEN 129
#define MAX_HEX_COUNT 30
#define _CRT_SECURE_NO_WARNINGS
#define MAT_SIZE 3

//1.
int main() {
	int A[MAT_SIZE][MAT_SIZE] = { 0 };
	int B[MAT_SIZE][MAT_SIZE] = { 0 };
	int i = 0, j = 0;

	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%dx%d:\t", i + 1, j + 1);
			scanf(" %d", &A[i][j]);
		}
	}
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			B[i][j] = 5 * A[i][j];
		}
	}
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%d ", B[i][j]);
		}
		printf("\n");
	}
}

//2.
int main() {
	int A[MAT_SIZE][MAT_SIZE] = { 0 };
	int B[MAT_SIZE][MAT_SIZE] = { 0 };
	int i = 0, j = 0;

	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%dx%d:\t", i + 1, j + 1);
			scanf(" %d", &A[i][j]);
		}
	}
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			B[i][j] = A[j][i];
		}
	}
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%d ", B[i][j]);
		}
		printf("\n");
	}
}

//3.
int main() {
	int A[MAT_SIZE][MAT_SIZE] = { 0 };
	int B[MAT_SIZE][MAT_SIZE] = { 0 };
	int C[MAT_SIZE][MAT_SIZE] = { 0 };
	int D[MAT_SIZE][MAT_SIZE] = { 0 };
	int i = 0, j = 0, temp=0, x=0;

	printf("Matrica A:\n");
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%dx%d:\t", i + 1, j + 1);
			scanf(" %d", &A[i][j]);
		}
	}
	printf("Matrica B:\n");
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%dx%d:\t", i + 1, j + 1);
			scanf(" %d", &B[i][j]);
		}
	}
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			C[i][j] = A[i][j] + B[i][j];
		}
	}
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			temp=0;
			for (x = 0; x < MAT_SIZE; x++) {
				temp += (A[i][x] * B[x][j]);
			}
			D[i][j] = temp;
		}
	}
	printf("Matrica D:\n");
	for (i = 0; i < MAT_SIZE; i++) {
		for (j = 0; j < MAT_SIZE; j++) {
			printf("%d ", D[i][j]);
		}
		printf("\n");
	}
}

//4.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <conio.h>
#include <ctype.h>
#define STR_LEN 129
#define MAX_HEX_COUNT 30
#define _CRT_SECURE_NO_WARNINGS

//1.
int main()
{
	char znak = '\0';

	printf("Unesi znak:\t\n ESC za prekid.\n");
		do {
			znak = _getche();
		} while (znak != 27);
}
//2.
int main()
{
	char original[STR_LEN] = "\0", copy[STR_LEN] = "\0";
	int i = 0, j=0;

	printf("Unesi tekst:\n");
	scanf(" %s", original);

	for (i = 0; i < strlen(original); i++) {
		if (!isdigit(original[i])) {
			copy[j] = original[i];
			j++;
		}
	}
	copy[j] = '\0';
	printf("%s", copy);
}
//3.
int main()
{
	char txt[STR_LEN] = "\0";
	int i = 0, j = 0;
	char upper = '\0';

	printf("Unesi tekst:\t");
	scanf(" %s", txt);
	//a)
	for (i = 0; i < strlen(txt); i++) {
		if (isalpha(txt[i])) {
			txt[j++] = txt[i];
		}
	}
	txt[j] = '\0';
	printf("Nakon prve operacije: %s\n", txt);
	//b
	j = 0;
	for (i = 0; i < strlen(txt); i++) {
		switch (toupper(txt[i])) {
		case 'A':
		case 'E':
		case 'I':
		case 'O':
		case 'U':
			break;
		default:
			txt[j++] = txt[i];
		}
	}
	txt[j] = '\0';
	printf("Nakon druge operacije: %s\n", txt);
//c
	for (i = 0; i < strlen(txt); i++) {
		if (isupper(txt[i])) {
			txt[i] = tolower(txt[i]);
		}
		else {
			txt[i] = toupper(txt[i]);
		}
	}
	printf("Nakon trece operacije: %s\n", txt);
}

//4.
int main() {
	int decVal = 0, i=0, temp=0;
	char revhexVal[MAX_HEX_COUNT] = "\0", hexMap[]="0123456789ABCDEF";

	printf("Unesi dekadski broj:\t");
	scanf(" %d", &decVal);

	while (decVal != 0) {
		revhexVal[i++] = hexMap[decVal % 16];
		decVal /= 16;
	}
	i--;
	printf("Hex broj:\n");
	while (i >= 0) {
		printf("%c\n", revhexVal[i--]);
	}
}

//1.
int main()
{
	int value[2] = { 0 };
	char op = '\0';
	double result = 0.0;
	
	printf("Unesi prvi broj:\n");
	scanf(" %d", &value[0]);
	printf("Unesi drugi broj:\n");
	scanf(" %d", &value[1]);
	printf("Odaberi operaciju:\n + -> zbrajanje\n - -> oduzimanje\n * -> mnozenje\n / -> dijeljenje\n");
	scanf(" %c", &op);
 
	switch (op) {
	case '+':
		result = value[0] + value[1];
		break;
	case '-':
		result = value[0] + value[1];
		break;
	case '*':
		result = value[0] * value[1];
		break;
	case '/':
		if (value[1] == 0) {
			printf("Nije moguce dijelit s nulom!\n");
			result = INT_MIN;
		}
		else {
			result = (double)value[0] / value[1];
		}
		break;
	default:
		printf("Pogresan unos!\n");
		result = INT_MIN;
	}
	printf("------------\n");
	printf("Izvrsena operacija: %c\n", op);
	printf("Konacan rezultat: %lf\n", result);
}
//2.
int main()
{
	int ocjene[20] = { 0 }, i = 0;
	int histogram[5] = { 0 };
 
	printf("Potrebno je unijeti 20 ocjena.\n");
	for (i = 0; i < 20; i++) {
		printf("Ocjena broj %d.\t", i + 1);
		scanf(" %d", &ocjene[i]);
		if (ocjene[i] < 1 || ocjene[i] > 5) {
			printf("Neispravan unos!\n");
			i--;
		}
	}
	for (i = 0; i < 20; i++) {
		histogram[ocjene[i] - 1]++;
	}
	printf("------------\n");
	for (i = 0; i < 5; i++) {
		printf("Broj ocjena %d: %d\n", i + 1, histogram[i]);
	}
}
//3.
int main()
{
	int niz[10] = { 0 };
	int i=0, j = 0;
	int min = 0, max = 0;
	int temp = 0;
 
	printf("Unesi 10 brojeva:\n");
	for (i = 0; i < 10; i++) {
		printf("Broj %d:\t", i + 1);
		scanf(" %d", &niz[i]);
	}
	min = niz[0];
	max = niz[0];
	for (i = 1; i < 10; i++) {
		if (niz[i] < min) {
			min = niz[i];
		}
		if (niz[i] > max) {
			max = niz[i];
		}
	}
	for (i = 0; i < 9; i++) {
		for (j = i + 1; j < 10; j++) {
			if (niz[i] > niz[j]) {
				temp = niz[i];
				niz[i] = niz[j];
				niz[j] = temp;
			}
		}
	}
	printf("--------------\n");
	printf("Minimalni broj: %d\n Maksimalni broj: %d\n", min, max);
	for (i = 1; i < 10; i++) {
		printf("%d\n", niz[i]);
	}
}

int main()
{
	int arr[5] = { 0 };
	int i = 0, j = 0, temp = 0;

	printf("Unesi 5 brojeva:\n");
	for (i = 0; i < 5; i++) {
		scanf(" %d", &arr[i]);
	}
	for (i = 0; i < 4; i++) {
		for (j = i + 1; j < 5; j++) {
			if (arr[i] > arr[j]) {
				temp = arr[i];
				arr[i] = arr[j];
				arr[j] = temp;
			}
		}
	}
	printf("------------\n");
	for (i = 0; i < 5; i++) {
		printf("%d\n", arr[i]);
	}
}

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define _CRT_SECURE_NO_WARNINGS

//1.
int main()
{
	float broj;
	printf("Unesite realan broj:\t");
	scanf("%f", &broj);

	if ((broj - (int)broj) >= 0.5)
		printf("%d", (int)broj + 1);
	else if ((broj - (int)broj) <= -0.5)
		printf("%d", (int)broj - 1);
	else
		printf("%d", int(broj));

}
//3.
int main()
{
	int broj, temp = 0;
	for (int i = 0; i < 10; i++)
	{
		printf("Unesi %d. broj.\n", i + 1);
		scanf("%d", &broj);
		printf("\n");
		if (broj % 3 == 0)
			temp++;
	}

	printf("%d unesena/ih brojeva djeljivo je s 3.\n", temp);
}
//4.
int main()
{
	char slovo; int br_H = 0, br_ms = 0;
	for (int i = 0; i < 10; i++)
	{
		printf("Unesi slovo:\t");
		scanf(" %c", &slovo);
		printf("\n");
		if (slovo == 'H')
			br_H++;
		if (slovo >= 'a' && slovo <= 'z')
			br_ms++;
	}

	printf("Slovo H uneseno je %d puta.\n", br_H);
	printf("Malo slovo uneseno je %d puta.\n", br_ms);
}
//5.
int main()
{
	int pass = 0, score = 0,cnt=0, i = 0; float avg = 0.0f;
	for (i = 0; i < 5; i++) {
		printf("Broj bodova:\t");
		scanf(" %d", &score);
		if (score < 0 || score > 100) {
			i--;
			continue;
		}
		if (score >= 50) {
			cnt++;
		}
		pass += score;
	}
		printf("Broj prolaznika: %d\n", cnt);
		avg = pass / 5.0f;
		printf("Prosjecan broj bodova: %f", avg);
}

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define _CRT_SECURE_NO_WARNINGS
//1.
int main() {
	int cnt = 0, sum = 0, num = 0; float aritm = 0.0;
 
	do {
		printf("Unesi broj\t");
		scanf("%d", &num);
		if (num == 0) {
			break;
		}
		cnt++;
		sum += num;
	} while (1);
	aritm = (float)sum / cnt;
	printf("Aritmeticka sredina je %f.\n", aritm);
}
//2.
int main()
{
	int br = 0, rem = 0;
	printf("Unesi broj:\t");
	scanf(" %d", &br);
	if (br < 0) {
		printf("- ");
		br *= -1;
	}
	do {
		rem = br % 10;
		printf("%d ", rem);
		br /= 10;
	} while (br != 0);
}
//3.
int main()
{
	int rnd = 0, guess = 0, cnt = 0;
 
	srand((unsigned)time(NULL));
	rnd = rand();
	do {
		printf("Unesi broj:\t");
		scanf(" %d", &guess);
		cnt++;
		if (guess < rnd) {
			printf("Random broj je veci od unesenog!\n");
		}
		else if (guess > rnd) {
			printf("Random broj je manji od unesenog!\n");
		}
 
	} while (rnd != guess);
	printf("BINGO!\n");
	printf("Potrebno je bilo %d pokusaja.\n", cnt);
}

//4.
int main()
{
	int temp;
	for (int i = 1; i <= 100; i++)
	{
		temp = 1;
		for (int j = 2; j < i; j++)
		{
			if ((i % j) == 0)
				temp = 0;
		}
		if (temp)
			printf("%d ", i);
	}
}

sdk_path="/Library/Developer/CommandLineTools/SDKs"

#include <stdio.h>

int main(){
  char str[20];
  
  fgets(str, 20, stdin); // read from stdin
  puts(str); // print read content out to stdout
  
  // open the file
  FILE *f = fopen("file.txt" , "r"); 
  
  // if there was an error
  if(f == NULL){
    perror("Error opening file"); // print error
    return(-1); 
  }
  // if there was no error
  else{ 
    fgets(str, 20, f); // read from file
    puts(str); // print read content out to stdout
  }
  
  fclose(f); // close file
  
  return(0);
}

#include "SevSeg.h"
SevSeg sevseg;

int LEDRa = 33;
int LEDGa = 32;

int LEDRb = 23;
int LEDGb = 22;

int LEDRc = 50;
int LEDGc = 51;

int LEDRd = 42;
int LEDGd = 43;

int IRa1 = 44;
int IRa2 = 52;

int IRb1 = 49;
int IRb2 = 48;

int IRc1 = 35;
int IRc2 = 37;

int IRd1 = 47;
int IRd2 = 46;

int RoadATraffic[] = {0, 0};
int RoadBTraffic[] = {0, 0};
int RoadCTraffic[] = {0, 0};
int RoadDTraffic[] = {0, 0};

char jam[] = {'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd', 'a', 'b', 'c', 'd'};

void setup() {
  pinMode (LEDRa, OUTPUT);
  pinMode (LEDGa, OUTPUT);

  pinMode (LEDRb, OUTPUT);
  pinMode (LEDGb, OUTPUT);

  pinMode (LEDRc, OUTPUT);
  pinMode (LEDGc, OUTPUT);

  pinMode (LEDRd, OUTPUT);
  pinMode (LEDGd, OUTPUT);

  pinMode (IRa1, INPUT);
  pinMode (IRa2, INPUT);

  pinMode (IRb1, INPUT);
  pinMode (IRb2, INPUT);

  pinMode (IRc1, INPUT);
  pinMode (IRc2, INPUT);

  pinMode (IRd1, INPUT);
  pinMode (IRd2, INPUT);

  byte numDigits = 2;
  byte digitPins[] = {11, 10};
  byte segmentPins[] = {9, 8, 6, 3, 4, 7, 2, 5};
  bool resistorsOnSegments = true;

  byte hardwareConfig = COMMON_CATHODE;
  sevseg.begin(hardwareConfig, numDigits, digitPins, segmentPins, resistorsOnSegments);
  sevseg.setBrightness(90);

  Serial.begin(9600); // open the serial port at 9600 bps:
}

static int counter = 5;
int jam_ind = 0;
int current_route = 0;

void loop() {
    //display();
    RoadATraffic[0] = (digitalRead (IRa1) != 1) ? ( 1 ) : ( 0 );
    RoadATraffic[1] = (digitalRead (IRa2) != 1) ? ( 1 ) : ( 0 );

    RoadBTraffic[0] = (digitalRead (IRb1) != 1) ? ( 1 ) : ( 0 );
    RoadBTraffic[1] = (digitalRead (IRb2) != 1) ? ( 1 ) : ( 0 );

    RoadCTraffic[0] = (digitalRead (IRc1) != 1) ? ( 1 ) : ( 0 );
    RoadCTraffic[1] = (digitalRead (IRc2) != 1) ? ( 1 ) : ( 0 );

    RoadDTraffic[0] = (digitalRead (IRd1) != 1) ? ( 1 ) : ( 0 );
    RoadDTraffic[1] = (digitalRead (IRd2) != 1) ? ( 1 ) : ( 0 );

    int sum1 = RoadATraffic[0] + RoadATraffic[1];
    int sum2 = RoadBTraffic[0] + RoadBTraffic[1];
    int sum3 = RoadCTraffic[0] + RoadCTraffic[1];
    int sum4 = RoadDTraffic[0] + RoadDTraffic[1];

    Serial.print(current_route);
    Serial.print('\n');
    Serial.print(jam_ind);
    Serial.print('\n');
    Serial.print('\n');

    change_route(jam[current_route]);
    display();
      
    if (sum1 >= sum2 && sum1 >= sum3 && sum1 >= sum4) {     // Road A Jam
      if (jam[current_route] == 'a' && counter == 1) {
        increase_jam_ind();
        jam[jam_ind] = 'a';
      } else if (jam[current_route] != 'a' && jam[jam_ind] != 'a') {
        increase_jam_ind();
        jam[jam_ind] = 'a';
      }
    }

    if (sum2 >= sum1 && sum2 >= sum3 && sum2 >= sum4) { // Road B Jam
      if (jam[current_route] == 'b' && counter == 1) {
        increase_jam_ind();
        jam[jam_ind] = 'b';
      } else if (jam[current_route] != 'b' && jam[jam_ind] != 'b') {
        increase_jam_ind();
        jam[jam_ind] = 'b';
      }
    }
    
    if (sum3 >= sum1 && sum3 >= sum2 && sum3 >= sum4) { // Road C Jam
      if (jam[current_route] == 'c' && counter == 1) {
        increase_jam_ind();
        jam[jam_ind] = 'c';
      } else if (jam[current_route] != 'c' && jam[jam_ind] != 'c') {
        increase_jam_ind();
        jam[jam_ind] = 'c';
      }
    }
      
    if (sum4 >= sum1 && sum4 >= sum2 && sum4 >= sum3) { // Road D Jam
      if (jam[current_route] == 'd' && counter == 1) {
        increase_jam_ind();
        jam[jam_ind] = 'd';
      } else if (jam[current_route] != 'd' && jam[jam_ind] != 'd') {
        increase_jam_ind();
        jam[jam_ind] = 'd';
      }
    }  
}

void display() {
  for (int h = 1; h<10000; h++){
    sevseg.setNumber(counter);
    sevseg.refreshDisplay();  
  }
  if (counter <= 0) {
    counter = 5;
    current_route++;
  }

  if (current_route > 15) { 
    current_route = 0;
  }
  
  counter--;
}

void change_route(char route) {
  switch (route) {
    case 'a':
      digitalWrite(LEDGa, HIGH);
      digitalWrite(LEDRa, LOW);
    
      digitalWrite(LEDGb, LOW);
      digitalWrite(LEDRb, HIGH);
    
      digitalWrite(LEDGc, LOW);
      digitalWrite(LEDRc, HIGH);
    
      digitalWrite(LEDGd, LOW);
      digitalWrite(LEDRd, HIGH);
      break;

    case 'b':
      digitalWrite(LEDGa, LOW);
      digitalWrite(LEDRa, HIGH);
    
      digitalWrite(LEDGb, HIGH);
      digitalWrite(LEDRb, LOW);
    
      digitalWrite(LEDGc, LOW);
      digitalWrite(LEDRc, HIGH);
    
      digitalWrite(LEDGd, LOW);
      digitalWrite(LEDRd, HIGH);
      break;

    case 'c':
      digitalWrite(LEDGa, LOW);
      digitalWrite(LEDRa, HIGH);
    
      digitalWrite(LEDGb, LOW);
      digitalWrite(LEDRb, HIGH);
    
      digitalWrite(LEDGc, HIGH);
      digitalWrite(LEDRc, LOW);
    
      digitalWrite(LEDGd, LOW);
      digitalWrite(LEDRd, HIGH);
      break;

    case 'd':
      digitalWrite(LEDGa, LOW);
      digitalWrite(LEDRa, HIGH);
    
      digitalWrite(LEDGb, LOW);
      digitalWrite(LEDRb, HIGH);
    
      digitalWrite(LEDGc, LOW);
      digitalWrite(LEDRc, HIGH);
    
      digitalWrite(LEDGd, HIGH);
      digitalWrite(LEDRd, LOW);
      break;
  }
}

void increase_jam_ind() {
  jam_ind++;
  if (jam_ind > 15) {
    jam_ind = 0;
  }
}

#include <linux/limits.h>

char current_path[PATH_MAX];