2021-05-06 17:33:56 +00:00
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package main
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import (
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"fmt"
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"runtime"
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2021-10-13 15:43:54 +00:00
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"sync"
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"time"
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2021-05-06 17:33:56 +00:00
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)
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var globalvar1 = 0
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var globalvar2 = 0
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func main() { // Position 0
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runtime.LockOSThread()
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globalvar2 = 1
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fmt.Printf("%d %d\n", globalvar1, globalvar2)
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globalvar2 = globalvar1 + 1
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globalvar1 = globalvar2 + 1
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fmt.Printf("%d %d\n", globalvar1, globalvar2) // Position 1
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2021-10-04 21:45:05 +00:00
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2021-05-06 17:33:56 +00:00
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globalvar2 = globalvar2 + 1 // Position 2
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globalvar2 = globalvar1 + globalvar2 // Position 3
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fmt.Printf("%d %d\n", globalvar1, globalvar2)
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globalvar1 = globalvar2 + 1
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fmt.Printf("%d %d\n", globalvar1, globalvar2)
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2021-10-04 21:45:05 +00:00
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2021-05-06 17:33:56 +00:00
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done := make(chan struct{}) // Position 4
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2021-10-13 15:43:54 +00:00
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var wg sync.WaitGroup
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for i := 0; i < 20; i++ {
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wg.Add(1)
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go waitfunc(i, &wg)
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}
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wg.Wait()
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2021-05-06 17:33:56 +00:00
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go f(done)
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<-done
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}
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func f(done chan struct{}) {
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runtime.LockOSThread()
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2021-10-04 21:45:05 +00:00
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globalvar1 = globalvar2 + 2
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2021-05-06 17:33:56 +00:00
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close(done) // Position 5
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}
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2021-10-13 15:43:54 +00:00
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func waitfunc(i int, wg *sync.WaitGroup) {
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runtime.LockOSThread()
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wg.Done()
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time.Sleep(50 * time.Second)
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}
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