#version 100

import std.reo;
import std.buf;

primitive main(in a, out b) {
    while (true) {
        sync {
            if (fires(a) && fires(b)) {
                msg x = get(a);
                short y = readShort(x, 0);
                y++;
                writeShort(x, 0, y);
                put(b, x);
            } else {
                assert !fires(a) && !fires(b);
            }
        }
    }
}