new

package main

import (
    "fmt"
)

const nBatchSize int = 2

func summ(a []int, r chan int) {

    summ := 0
    for _, v := range a {
        summ += v
    }

    r <- summ
}

func main() {

    a := make([]int, 0, 100)
    for i := 0; i < 100; i++ {
        a = append(a, i)
    }

    r := make(chan int)
    nBatch := int(len(a) / nBatchSize)

    for j := 0; j < nBatch; j++ {
        go summ(a[j*nBatchSize:(j+1)*nBatchSize], r)
    }

    total := 0
    for i := 0; i < nBatch; i++ {
        summ := <-r
        total += summ
    }

    fmt.Println("Total =", total)

}