题目序号:(6609)
题目来源:滴滴
频次:1
答案1:(peace)
1)用channel进行同步(该方法需要知道goroutine的数量)
func main() {
ch := make(chan int, 2)
go func() {
for i := 0; i < 10; i++ {
time.Sleep(1 * time.Second)
fmt.Println("go routine1", i)
}
ch <- 1
}()
go func() {
for i := 0; i < 10; i++ {
time.Sleep(1 * time.Second)
fmt.Println("go routine2", i)
}
ch <- 2
}()
// 等待
for i := 0; i < 2; i++ {
<-ch
}
fmt.Println("main exist")
}
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2)用sync.WaitGroup
package main
import "fmt"
import "time"
import "sync"
func main() {
var wg sync.WaitGroup
for i := 0; i < 10; i++ {
wg.Add(1)
go func(i int) {
defer wg.Done()
time.Sleep(1 * time.Second)
fmt.Println(i)
}(i)
}
wg.Wait() // 等待
fmt.Println("main exist")
}
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