package main

import "fmt"

func sum(s []int, c chan int) {
    sum := 0
    for _, v := range s {
        sum += v
    }
    c <- sum // send sum to c
}

func main() {
    s := []int{7, 2, 8, -9, 4, 0}
    c := make(chan int)
    go sum(s[:len(s) / 2], c)
    go sum(s[len(s) / 2:], c)
    x, y := <-c, <-c // receive from c

    fmt.Println(x, y, x + y)
}