Kaktus - Guess the number

#include <iostream>
#include <ctime>
#include <stdlib.h>
#include <string>

using namespace std;

void game();

int main() {
    string menu;
    cout << "Welcome to 'Guess a number'" << endl;
    cout << "Write 'Start' to start the game!" << endl;
    cin >> menu;

    if(menu == "start" || menu == "Start") {
        game();
    } else {
        return 0;
    }
}

void game() {
    srand(time(NULL));
    int high;
    int low;
    int guess;
    int number;
    bool gameLoop = true;

    cout << "Write down the highest number you want to guess: ";
    cin >> high;
    cout << endl;
    cout << "Write down the lowest number you want to guess: ";
    cin >> low;
    cout << endl;

    guess = rand() % high + low;

    while(gameLoop) {
        cout << "Guess a number: ";
        cin >> number;

        if(number > guess) {
            cout << endl << "<" << endl;
        } else if(number< guess) {
            cout << endl << ">" << endl;
        } else if(number == guess) {
            gameLoop = false;
            cout << "You won!" << endl;
        }
    }
}