factorial c++ recursive function code example

Example 1: factorial c++ without using function

#include <iostream>
using namespace std;

int main()
{
	unsigned int num; //unsigned is used for not taking negetive values.
	unsigned long long factorial = 1; //Since the factorial a number can be large, so long long data type is used.
	cout << "Give me any positive number :	";
	cin >> num;

	for (int i = 1; i <= num; i++) {
		factorial = factorial * i;
	}
	cout << "Factorial of the given number is: " << factorial;
}

Example 2: c++ factorial

#include <cmath>

int fact(int n){
    return std::tgamma(n + 1);  
}    
// for n = 5 -> 5 * 4 * 3 * 2 = 120 
//tgamma performas factorial with n - 1 -> hence we use n + 1