try yourself |run program

#include <stdio.h> 
#include <conio.h> 
void main(){
 int a;
 int b;
 int rem;
 clrscr();
 printf("Enter value of a: ");
 scanf("%d",&a);
 printf("\n Enter value of b: ");
 scanf("%d",&b);
 rem = a % b;
 printf("\n remainder = %d",rem);
 getch();
}

Program Output

Enter value of a: 25 
Enter value of b: 7 
remainder = 4