1.1 Prepare Student Grade Book

#include<stdio.h>
#include<conio.h>
int main()
{
	int rows,i,j,ch,data;
	int arr[20][6];
	clrscr();
	printf("Enter number of Students : ");
	scanf("%d",&rows);
	for(i=0;i<rows;i++)
	{
		for(j=0;j<5;j++)
		{
			int marks;
			printf("Enter marks of %d student and %d subject : ",i+1,j+1);
			scanf("%d",&marks);
			arr[i][j]=marks;
		}
	}

	for(i=0;i<rows;i++)
	{
		int sum=0;
		for(j=0;j<5;j++)
		{
			sum+=arr[i][j];
		}
		printf("Total of %dth student is : %d \n",i+1,sum);
		printf("Average of %dth student is %d\n",i+1,sum/5);
	}
	printf("Do you want to change data Press 1 for Yes and 0 for No :");
	scanf("%d",&ch);
	if(ch)
	{
		printf("Type student No :");
		scanf("%d",&i);
		printf("Type subject No :");
		scanf("%d",&j);
		printf("Enter new data :");
		scanf("%d",&data);
		arr[i-1][j-1]=data;

		//Print Updated Data
		for(i=0;i<rows;i++)
		{
			for(j=0;j<5;j++)
			{
				printf("%d ",arr[i][j]);
			}
			printf("\n");
		}
	}
	getch();
	return 0;

}