C++ Factorial

Program written in C++ to calculate  factorial.

// ? 2017 TheFlyingKeyboard and released under MIT License
// theflyingkeyboard.net

#include <iostream>

using namespace std;

unsigned long long factorial(unsigned int n);

int main(){
  unsigned int n;
  
  cout << "Enter a number: ";
  cin >> n;
  
  cout << "Factorial of " << n << " is equal to " << factorial(n) << endl;
  
  return 0;
}

unsigned long long factorial(unsigned int n) {
  unsigned long long fact = 1;
    
    for(unsigned int i = 2; i <= n; i++){
      fact *= i;
    }
    
    return fact;
}