C++ program to reverse the input number by for, while and do while loop

reverse_number.cpp

//By Muhammad Umer Farooq
#include <iostream>

namespace ReverseNumber
{
	int rem = 0; int rev = 0;
	int for_loop(int n)
	{
		for (n; n != 0; n /= 10) { // for (n; n > 0; n /= 10), for (;n != 0; n /= 10)
			rem = n % 10;
			rev = rev * 10 + rem;		
		}
		return rev;
	}
	
	int while_loop(int n)
	{
		rem = rev = 0;
		while (n != 0) { //while (n > 0)
			rem = n % 10;
			rev = rev * 10 + rem;
			n /= 10;
		}
		
		return rev;
	}
	
	int do_while_loop(int n)
	{
		rem = rev = 0;
		do {
			rem = n % 10;
			rev = rev * 10 + rem;
			n /= 10;	
		} while(n != 0); // while (n > 0);
		
		return rev;
	}	
}

int main()
{
	int n;
	std::cout << "Enter number to reverse \t";
	std::cin >> n;
	
	std::cout << "For loop: " << ReverseNumber::for_loop(n) << std::endl;
	std::cout << "While loop: " << ReverseNumber::while_loop(n) << std::endl;
	std::cout << "Do While loop: " << ReverseNumber::do_while_loop(n);
	
	return 0;
}