R/P/S Functional - Reddit

#include <iostream>
#include <cstdlib>
#include <ctime>
#include <string>
using namespace std;

void playGame();
int genRandNum();
string userChooses();
bool playAgain();

bool playAgain() {
    string stayOrGo;
    do {
        cout << "\nType 'y' to play again, 'n' to quit.\n" << endl;
        cin >> stayOrGo;
        if (stayOrGo != "y" && stayOrGo != "n") {
            cout << "\nThat is not correct input." << endl;
        }
    } while (stayOrGo != "y" && stayOrGo != "n");

    return stayOrGo == "y";
}

int genRandNum() {
    int randomNumber;
    srand(time(0));
    randomNumber = rand() % 3 + 1;
    return randomNumber;
}

string userChooses() {
    string userChoice;
    do {
        cout << "\nDo you choose 'rock', 'paper' or 'scissors'?\n\n";
        cin >> userChoice;
        if (userChoice != "rock"
            && userChoice != "paper"
            && userChoice != "scissors") {
            cout << "\nThat is not correct input." << endl;
        }
    } while (userChoice != "rock"
        && userChoice != "paper"
        && userChoice != "scissors");
    cout << "\nYou have chosen: " << userChoice << endl;
    return userChoice;
}

string computerChooses(int randomNumber) {
    string computerChoice;
    if (randomNumber == 1) {
        computerChoice = "rock";
        cout << "\nThe computer has chosen: " << computerChoice << endl;
    }
    else if (randomNumber == 2) {
        computerChoice = "paper";
        cout << "\nThe computer has chosen: " << computerChoice << endl;
    }
    else {
        computerChoice = "scissors";
        cout << "\nThe computer has chosen: " << computerChoice << endl;
    }
    return computerChoice;
}

void compareChoices(string userChoice, string computerChoice) {
    // If userChoice is rock
    if (userChoice == "rock") {
        if (computerChoice == "paper") {
            cout << "\nPaper beats rock, you lose!" << endl;
        } else if(computerChoice == "scissors") {
            cout << "\nRock beats scissors, you win!" << endl;
        }
        else {
            cout << "\nIt's a tie!" << endl;
        }
    }
    // If userChoice is paper
    if (userChoice == "paper") {
        if (computerChoice == "scissors") {
            cout << "\nScissors beats paper, you lose!" << endl;
        }
        else if (computerChoice == "rock") {
            cout << "\nPaper beats rock, you win!" << endl;
        }
        else {
            cout << "\nIt's a tie!" << endl;
        }
    }
    // If userChoice is scissors
    if (userChoice == "scissors") {
        if (computerChoice == "rock") {
            cout << "\nRock beats scissors, you lose!" << endl;
        }
        else if (computerChoice == "paper") {
            cout << "\nScissors beats paper, you win!" << endl;
        }
        else {
            cout << "\nIt's a tie!" << endl;
        }
    }
}

void playGame() {
    string userChoice = userChooses();
    string computerChoice = computerChooses(genRandNum());
    compareChoices(userChoice, computerChoice);
}

int main() {
    do {
        playGame();
    } while (playAgain());
    cout << "\nYou have chosen to exit the game.\n" << endl;
    system("PAUSE");
    return 0;
}