package main

import (
	"fmt"
	"log"
)

func main() {
	N := 100
	P := 3
	q := make(chan int)
	scatter(N, P, q)
	gather(N, P, q)
}

func scatter(N, P int, q chan int) {
	for i := 0; i < P; i++ {
		go _scatter(i, N, P, q)
	}
}

func _scatter(i, N, P int, q chan int) {
	start := i * (N / P)
	chunk := N / P
	if i == P-1 {
		chunk += N % P
	}
	ttl := 0
	for j := start; j <= start+chunk; j++ {
		ttl += j
	}
	log.Println(i, N, P, q, start, start+chunk, ttl)
	q <- ttl
}

func gather(N, P int, q chan int) {
	ttl := 0
	for i := 0; i < P; i++ {
		ttl += <-q
	}
	fmt.Println("go", ttl)
}