#include<stdio.h>
void main()
{
    int n,r,ncr;
    printf("Enter N and R values: ");
    scanf("%d %d",&n,&r);
    ncr=fact(n)/(fact(r)*fact(n-r));
    printf("The NCR of %d and %d is %d",n,r,ncr);
}

// x is a formal parameter or dummy parameter
// Calculate using n!/(n-r)!*r!
int fact(int x)
{
    int i=1;
    while(x!=0)
    {
        i=i*x;
        x--;
    }
    return i;
}

  OUTPUT:

Enter N and R values: 5 2
The NCR of 5 and 2 is 10