tour.golang.org/concurrency/8-2

package main

import (
  "golang.org/x/tour/tree"
  "fmt"
)

func Walk(name string, t *tree.Tree, ch chan int) {
  if t.Left != nil {
    Walk(name, t.Left, ch)
  }
  ch <- t.Value
  if t.Right != nil {
    Walk(name, t.Right, ch)
  }
}
var tree1 = tree.Tree{
  Left: &tree.Tree{
    Value: 1,
    Right: &tree.Tree{
      Value: 2,
    },
  },
  Value: 3,
  Right: &tree.Tree{
    Left: &tree.Tree{
      Value: 5,
    },
    Value: 8,
  },
}
var tree2 = tree.Tree{
  Left: &tree.Tree{
    Left: &tree.Tree{
      Value: 1,
    },
    Value: 2,
    },
  Value: 3,
}

func Same(t1, t2 *tree.Tree) bool {
  var ch1 = make(chan int, 1)
  go func() {
    Walk("t1", t1, ch1)
    fmt.Println("close 1")
    close(ch1)
  } ()

  var ch2 = make(chan int, 1)
  go func() {
      Walk("t2", t2, ch2)
      fmt.Println("close 2")
      close(ch2)
  } ()

  for i:= 0; i<5; i++ {
    v1, ok1 := <-ch1
    v2, ok2 := <-ch2
    if !ok1 || !ok2 || v1 != v2 {
      return false
    }
  }
  return true
}
func main() {
  result := Same(&tree1, &tree2)
  fmt.Println("result", result)
}