#!/usr/bin/env python
# Copyright 2008-2010 Isaac Gouy
# Copyright (c) 2013, 2014, Regents of the University of California
# Copyright (c) 2017, 2021, Oracle and/or its affiliates.
# All rights reserved.
#
# Revised BSD license
#
# This is a specific instance of the Open Source Initiative (OSI) BSD license
# template http://www.opensource.org/licenses/bsd-license.php
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#   "The Computer Language Shootout Benchmarks" nor the name "nanobench" nor the
#   name "bencher" nor the names of its contributors may be used to endorse or
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# The Computer Language Benchmarks Game
# http://shootout.alioth.debian.org/
#
# contributed by Daniel Nanz 2008-03-11
# --------------------------------------------
# Coroutines via enhanced generators
# (http://www.python.org/dev/peps/pep-0342/)

import itertools


def main(n, n_threads=503, cycle=itertools.cycle):
    def worker(worker_id):
        n = 1
        while True:
            if n > 0:
                n = (yield (n - 1))
            else:
                print(worker_id)
                return


    threadRing = [worker(w) for w in range(1, n_threads + 1)]
    for t in threadRing: foo = next(t)            # start exec. gen. funcs
    sendFuncRing = [t.send for t in threadRing]   # speed...
    for send in cycle(sendFuncRing):
        try:
            n = send(n)
        except StopIteration:
            break


def __benchmark__(num=100):
    main(num)
