Sum_Factorial.cpp

#include <iostream>
using namespace std;
int sum(int n) {
    if(n==0)
        return 0;
    else
        return n+sum(n-1);
}
int main()
{
    int putNum;
    cout<<"Input\t:  ";
    cin >> putNum;
    cout<<"Result\t:  "<<sum(putNum)<<endl;
    return 0;
}