mirror of
https://github.com/golang/go
synced 2024-11-25 10:38:00 -07:00
be2edb5761
plus significant hand editing.
Back to T{x} for composite literals.
R=r
OCL=25612
CL=25632
52 lines
1.3 KiB
Go
52 lines
1.3 KiB
Go
// $G $D/$F.go && $L $F.$A && ./$A.out
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// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// This version generates up to 100 and checks the results.
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// With a channel, of course.
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package main
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// Send the sequence 2, 3, 4, ... to channel 'ch'.
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func Generate(ch chan<- int) {
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for i := 2; ; i++ {
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ch <- i // Send 'i' to channel 'ch'.
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}
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}
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// Copy the values from channel 'in' to channel 'out',
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// removing those divisible by 'prime'.
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func Filter(in <-chan int, out chan<- int, prime int) {
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for {
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i := <-in; // Receive value of new variable 'i' from 'in'.
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if i % prime != 0 {
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out <- i // Send 'i' to channel 'out'.
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}
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}
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}
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// The prime sieve: Daisy-chain Filter processes together.
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func Sieve(primes chan<- int) {
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ch := make(chan int); // Create a new channel.
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go Generate(ch); // Start Generate() as a subprocess.
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for {
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prime := <-ch;
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primes <- prime;
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ch1 := make(chan int);
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go Filter(ch, ch1, prime);
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ch = ch1
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}
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}
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func main() {
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primes := make(chan int);
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go Sieve(primes);
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a := []int{2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97};
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for i := 0; i < len(a); i++ {
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if <-primes != a[i] { panic(a[i])}
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}
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sys.Exit(0);
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}
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