Factorial in C++

Published on 09 October 2019 (Updated: 09 October 2019)

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 11:12:44. As a result, documentation below may be outdated.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

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