mirror of
https://github.com/golang/go
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2ccd20a646
Fixes #1742. I hope. Also this picks up an update to go_tutorial.html that should already have happened. R=brainman, rsc, peterGo CC=golang-dev https://golang.org/cl/4452050
52 lines
901 B
Go
52 lines
901 B
Go
// 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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package main
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import "fmt"
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// Send the sequence 2, 3, 4, ... to returned channel
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func generate() chan int {
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ch := make(chan int)
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go func(){
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for i := 2; ; i++ {
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ch <- i
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}
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}()
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return ch
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}
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// Filter out input values divisible by 'prime', send rest to returned channel
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func filter(in chan int, prime int) chan int {
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out := make(chan int)
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go func() {
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for {
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if i := <-in; i % prime != 0 {
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out <- i
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}
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}
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}()
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return out
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}
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func sieve() chan int {
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out := make(chan int)
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go func() {
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ch := generate()
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for {
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prime := <-ch
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out <- prime
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ch = filter(ch, prime)
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}
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}()
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return out
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}
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func main() {
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primes := sieve()
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for i := 0; i < 100; i++ { // Print the first hundred primes.
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fmt.Println(<-primes)
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}
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}
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