Choose k objects from n distinct objects

Write a C program that calculates the number of ways to choose k objects from n distinct objects. 'k' and 'n' both are integers.

Input Format:

First line contains the value of n, where 0<=n<=10

Second line contains the value of k, where k>=0

Output Format:

One line containing the number of ways to chose the objects

Note: In this question you are not given main() so you have to write the complete program.

#include<stdio.h>

long fact(long a);

int main()

{int n,k,temp;

scanf("%d",&n);

scanf("%d",&k);

long int d,den1,den2,ans1;

d=fact(n);

den1=fact(k);

temp=n-k;den2=fact(temp);

ans1=den1*den2;

ans1=d/ans1;

printf("%ld",ans1);

return 0;

}

long fact(long a)

{int i;long int ans=1;

for(i=1;i<=a;i++)

ans=ans*i;

return ans;

}