[C++]Rock-Paper-Scissors

#include "stdafx.h" //For the console application
#include <iostream> //For cout and cin - aka: Input/Output
#include <string> //For string - aka: text
 
using namespace std;
 
string AI()
{
    /*
    0 - Rock
    1 - Paper
    2 - Scissors
    */
 
    int r = rand() % 3; //returns 0 - 2
    if (r == 0)
    {
        return "rock";
    }
    else if(r == 1)
    {
        return "paper";
    }
    else
    {
        return "scissors";
    }
}
 
int _tmain(int argc, _TCHAR* argv[])
{
    //Set up a random seed
    srand (0);
 
    //Loop indefinately
    while (true == true)
    {
        string user_input = "";
 
        //Loop until user_input isn't empty
        while (user_input == "")
        {
            cout << "Please type in: rock, paper, or scissors" << "\n";
            cin >> user_input;
            if (user_input != "rock" && user_input != "paper" && user_input != "scissors")
            {
                user_input = "";
                cout << "Invalid input." << "\n" << "\n";
            }
        }
 
        string comp_input = AI();
 
        //Dish out the results
        cout << "You picked: " << user_input << "\n" << "The computer picked: " << comp_input << "\n";
        if (user_input == comp_input)
        {
            cout << "It's a draw." << "\n" << "\n";
        }
        else if (user_input == "rock" && comp_input == "paper" || user_input == "paper" && comp_input == "scissors" || user_input == "scissors" && comp_input == "rock")
        {
            cout << "You lose..." << "\n" << "\n";
        }
        else if (user_input == "rock" && comp_input == "scissors" || user_input == "paper" && comp_input == "rock" || user_input == "scissors" && comp_input == "paper")
        {
            cout << "You won!" << "\n" << "\n";
        }
    }
    return 0;
}