C++ Program to Find Factorial of a Given Number Using Recursion

What is recursion?

Function calling it shelf is called recursion.

Program:

#include <iostream>
using namespace std;

int factorial (int n)
{
  if (n < 1)
    return 1;

  return n * factorial (n - 1); //recursively calling factorial function till n > 1
}

int main ()
{
  int n;
  
  cout << "Enter a number: ";
  cin >> n;
  
  cout << "Factorial of " << n <<" is " << factorial (n);    //function call

  return 0;
}

Output:

Enter a positive integer: 5
Factorial of 5 is 120