Q 1.
#include <stdio.h>
#include <stdlib.h>
#define MAX_SIZE 3

int stack [MAX_SIZE];
int top = -1;

void push(int value) 
{
    if(top==MAX_SIZE-1) {
        printf("Stack Overflow (Full): Cannot Push Element (%d) onto the stack.\n", value);
    }
    else {
        top++;
        stack[top] = value;
        printf("Element (%d) Pushed Onto The Stack.\n", value);
    }
}

void pop() 
{
    if(top == -1) {
        printf("Stack Underflow (Empty): Cannot Pop Element From The Stack.\n");
    }
    else {
        printf("\nElement (%d) Popped From The Stack.\n", stack[top]);
        top--;
    }
}

void display()
{
    if(top == -1) {
        printf("Stack is Empty.\n");
    }
    else {
        printf("Stack Elements are: ");
        for(int i=top; i>=0; i--) {
            printf("%d, ",stack[i]);
        }
        printf("\n");
    }
}

int main() {
    
    push(10);
    push(20);
    display();
    push(50);
    push(100);
    display();

    pop();
    display();
    pop();
    pop();
    display();

    return 0;
}

//OUTPUT:
Element (10) Pushed Onto The Stack.
Element (20) Pushed Onto The Stack.
Stack Elements are: 20, 10, 
Element (50) Pushed Onto The Stack.
Stack Overflow (Full): Cannot Push Element (100) onto the stack.
Stack Elements are: 50, 20, 10, 

Element (50) Popped From The Stack.
Stack Elements are: 20, 10, 

Element (20) Popped From The Stack.

Element (10) Popped From The Stack.
Stack is Empty.


Q3. 
#include <stdio.h>
#include <stdlib.h>
#define MAX_SIZE 100

char stack[MAX_SIZE];
int top = -1;
void push(char data) {
    if (top == MAX_SIZE - 1) {
        printf("Overflow stack!\n");
        return;
    }
    top++;
    stack[top] = data;
}

char pop() {
    if (top == -1) {
        printf("Empty stack!\n");
        return ' ';
    }
    char data = stack[top];
    top--;
    return data;
}

int is_matching_pair(char char1, char char2) {
    if (char1 == '(' && char2 == ')') {
        return 1;
    } else if (char1 == '[' && char2 == ']') {
        return 1;
    } else if (char1 == '{' && char2 == '}') {
        return 1;
    } else {
        return 0;
    }
}
int isBalanced(char* text) {
    int i;
    for (i = 0; i < strlen(text); i++) {
        if (text[i] == '(' || text[i] == '[' || text[i] == '{') {
            push(text[i]);
        } else if (text[i] == ')' || text[i] == ']' || text[i] == '}') {
            if (top == -1) {
                return 0;
            } else if (!is_matching_pair(pop(), text[i])) {
                return 0;
            }
        }
    }
    if (top == -1) {
        return 1;
    } else {
        return 0;
    }
}

int main() {
   char text[MAX_SIZE];
   printf("Input an expression in parentheses: ");
   scanf("%s", text);
   if (isBalanced(text)) {
       printf("The expression is balanced.\n");
   } else {
       printf("The expression is not balanced.\n");
   }
   return 0;
}
//OUTPUT:
Input an expression in parentheses: {[({[]})]}
The expression is balanced.
Input an expression in parentheses: [{[}]]
The expression is not balanced.