C++ Program to calculate Permutation and Combination [DEVCPP/GCC]

PERMUTATION

Formula to find number of different permutations of n distinct objects taken r at a time is  

COMBINATION

Formula to find number of different combinations of n distinct objects taken r at a time is

PROGRAM

//Program to calculate Permutation and Combination

#include<iostream>

using namespace std;

int fact(int num) 

{

         if(num==1) 

        {

              return 1;

        }

        else 

        {

             return num * fact(num-1);

        }

}

int main() 

{

       int n,r,nPr,nCr;

       cout<<"Enter n: ";

       cin>>n;

       

       cout<<"Enter r: ";

       cin>>r;

       nPr=fact(n)/fact(n-r);

       nCr=nPr/fact(r);

       cout<<"nPr is: "<<nPr<<endl;

       cout<<"nCr is: "<<nCr;

       return 0;

}

OUTPUT