factorial recursive C code example

Example 1: find factoril in C using recursion

#include<stdio.h>
fact(int i, int k){
    k=k*i;
    i--;
    if(i==0){
        return k;
    }
    else{
        fact(i, k);
    }
}
int main()
{
    int k = 1, i, factorial;
    scanf("%d",&i);
    factorial = fact(i, k);
    printf("%d\n",factorial);
    return 0;
}

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