Factorial in C++

Published on 28 April 2022 (Updated: 02 February 2023)

Factorial in C++

Welcome to the Factorial in C++ page! Here, you’ll find the source code for this program as well as a description of how the program works.

Current Solution

#include <iostream>
#include <cstdlib>
using namespace std;

int main(int argc, char *argv[])
{
    if (argc < 2 || std::string(argv[1]) == "")
    {
        cout << "Usage: please input a non-negative integer" << endl;
        return 1;
    }

    int n = atoi(argv[1]);
    if (n == 0 && std::string(argv[1]) != "0")
    {
        cout << "Usage: please input a non-negative integer" << endl;
        return 1;
    }
    if (n < 0)
    {
        cout << "Usage: please input a non-negative integer" << endl;
        return 1;
    }
    int i, fact = 1;
    for (i = 1; i <= n; i++)
    {
        fact = fact * i;
    }
    cout << fact << endl;
    return 0;
}

Factorial in C++ was written by:

If you see anything you’d like to change or update, please consider contributing.

Note: The solution shown above is the current solution in the Sample Programs repository as of Oct 10 2022 16:05:09. The solution was first committed on Oct 09 2019 11:00:44. As a result, documentation below may be outdated.

How to Implement the Solution

No ‘How to Implement the Solution’ section available. Please consider contributing.

How to Run the Solution

No ‘How to Run the Solution’ section available. Please consider contributing.