package main

import (
	"fmt"
	"math"
	"time"
)

func sum(a []int, c chan int) {
	sum := 0
	for _, v := range a {
		sum += v
	}
	to_sleep := time.Duration(100*math.Abs(float64(sum))) * time.Millisecond
	fmt.Printf("Sleeping %s...\n", to_sleep)
	time.Sleep(to_sleep)
	c <- sum
}

func main() {
	a := []int{7, 2, 8, -9, 4, 0}

	c := make(chan int)
	go sum(a[:len(a)/2], c)
	go sum(a[len(a)/2:], c)
	x := <-c
	fmt.Printf("x = %d\n", x)
	y := <-c
	fmt.Printf("y = %d\n", y)
	fmt.Println(x, y, x+y)
}