Pool Model

#include <iostream>
#include <thread>
#include <mutex>

std::mutex mtx;

void waterStream(double speed, double *pool) {
    for (;;) {
        _sleep(1000);
        *pool += speed;
    }
}

void PoolModel(double *waterLevel) {
    for (;;) {
        _sleep(1000);
        if (*waterLevel < 0)
            *waterLevel = 0;
        system("cls");
        std::cout << "action" << std::endl;
        std::cout << "water level: " << *waterLevel << std::endl;
    }
}

int main() {
    mtx.lock();

    double waterLevel = 0;

    std::thread pool(PoolModel, &waterLevel);
    std::thread first(waterStream, 1.1, &waterLevel);
    std::thread second(waterStream, -1, &waterLevel);

    pool.join();
    first.join();
    second.join();

    return 0;
}