package main

import (
  "fmt"
)

func main() {
  a := 1
  b := 2

  operationDone := make(chan bool)
  go func() {
    b = a * b

    operationDone <- true
  }()

  <-operationDone

  a = b * b

  fmt.Println("Hit Enter when you want to see the answer")
  fmt.Scanln()

  fmt.Printf("a = %d, b = %d\n", a, b)
}