Go time Package Sleep

package main /*from  www  . java2 s  .c o m*/

import ( 
    "fmt" 
    "time" 
    "math/rand" 
) 

func f(n int) { 
    for i  := 0; i < 10; i++ { 
        fmt.Println(n, ":", i) 
        amt  := time.Duration(rand.Intn(250)) 
        time.Sleep(time.Millisecond * amt) 
    } 
} 

func main() { 
    for i  := 0; i < 10; i++ { 
        go f(i) 
    } 
    var input string 
    fmt.Scanln(&input) 
}