两个协程交替输出1-20

package main

import (
    "fmt"
    "runtime"
    "time"
)

func main() {
    runtime.GOMAXPROCS(1)
    go func() {
        for i := 1; i <= 10; i++ {
            fmt.Println(2*i - 1)
            runtime.Gosched()
        }
    }()
    go func() {
        for i := 1; i <= 10; i++ {
            fmt.Println(2 * i)
            runtime.Gosched()
        }
    }()
    time.Sleep(3 * time.Second)
}

原理：runtime.GOMAXPROCS(1)设置单核，runtime.Gosched()让出时间片