CHOOSE K OBJECTS FROM N DISTINCT OBJECT

• Problem Description

  
  Description 
  
  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.

• CODING ARENA

• #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;

  }

  
  

• Test Case 1

  
  Input (stdin)

  4
  
  2
  
  

  Expected Output

  6

• Test Case 2

  
  Input (stdin)

  2
  
  1
  
  

  Expected Output

  2