import stackless


def setup(N):
    in_chan = stackless.channel()
    out_chan = init(N-1, in_chan)
    return in_chan, out_chan


def run(N, M, in_chan, out_chan):
    send_message(out_chan, 0)
    count = manager(M-1, in_chan, out_chan)
    assert count == (N * M)  # Check for correct number of messages


def init(N, out_chan):
    while N > 0:
        in_chan = stackless.channel()
        stackless.tasklet(worker)(in_chan, out_chan)
        out_chan = in_chan
        N -= 1
    return out_chan


def manager(M, in_chan, out_chan):
    while M > 0:
        relay_message(in_chan, out_chan)
        M -= 1
    msg = in_chan.receive()
    return msg


def worker(in_chan, out_chan):
    while True:
        relay_message(in_chan, out_chan)


def send_message(chan, msg):
    chan.send(msg + 1)


def relay_message(in_chan, out_chan):
    msg = in_chan.receive()
    send_message(out_chan, msg)


if __name__ == '__main__':
    from ring_common import get_args, get_times, print_results

    N, M = get_args()

    (in_chan, out_chan), setup_cpu, setup_elapsed = get_times(setup, N)

    stackless.tasklet(run)(N, M, in_chan, out_chan)
    run_cpu, run_elapsed = get_times(stackless.run)[1:]

    print_results(N, M, setup_cpu, setup_elapsed, run_cpu, run_elapsed)