import core.thread;
import std.stdio;

class ThreadA : Thread {
    public this() {
        super(&run);
    }

    private void run() {
        for(uint i = 0; i < 10; i++) {
            Thread.sleep(30_000_000);
            writeln("ThreadA is runnin'.");
        }
    }
}

class ThreadB : Thread {
    public this() {
        super(&run);

        Thread a = new ThreadA();
        a.start();
    }

    private void run() {
        for(uint i = 0; i < 10; i++) {
            Thread.sleep(10_000_000);
            writeln("ThreadB is runnin'.");
        }
    }
}

int main(string[] args) {
    Thread b = new ThreadB();
    b.start();

    return 0;
}