mirror of
https://github.com/golang/go
synced 2024-11-26 18:26:48 -07:00
50 lines
929 B
Go
50 lines
929 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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// Send the sequence 2, 3, 4, ... to returned channel
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func Generate() *chan int {
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ch := new(chan int);
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go func(ch *chan int){
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for i := 2; ; i++ {
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ch <- i
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}
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}(ch);
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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 := new(chan int);
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go func(in *chan int, out *chan int, prime int) {
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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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}(in, out, prime);
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return out;
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}
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func Sieve() *chan int {
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out := new(chan int);
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go func(out *chan int) {
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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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}(out);
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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 {
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print(<-primes, "\n");
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}
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}
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