package main

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

func get_sum_of_divisible(num int, divider int, resultChan chan int) {
    sum := 0
    for value := 0; value < num; value++ {
        if value%divider == 0 {
            sum += value
        }
    }
    resultChan <- sum
}

func main() {
    runtime.GOMAXPROCS(runtime.NumCPU())
    LIMIT := 1000
    //用于被15除结果
    job1 := make(chan int, 1)
    //用于被3，5除结果
    job2 := make(chan int, 2)

    t_start := time.Now()
    go get_sum_of_divisible(LIMIT, 15, job1)
    go get_sum_of_divisible(LIMIT, 3, job2)
    go get_sum_of_divisible(LIMIT, 5, job2)

    sum15 := <-job1
    sum3, sum5 := <-job2, <-job2

    sum := sum3 + sum5 - sum15
    t_end := time.Now()
    fmt.Println(sum)
    fmt.Println(t_end.Sub(t_start))
}