https://tour.golang.org/concurrency/8

concurrency-exercise.go

package main

import (
	"fmt"

	"golang.org/x/tour/tree"
)

// Walk walks the tree t sending all values
// from the tree to the channel ch.
func Walk(t *tree.Tree, ch chan int) {
	walk(t, ch)
	close(ch)
}

func walk(t *tree.Tree, ch chan int) {
	if t == nil {
		return
	}

	walk(t.Left, ch)
	ch <- t.Value
	walk(t.Right, ch)
}

// Same determines whether the trees
// t1 and t2 contain the same values.
func Same(t1, t2 *tree.Tree) bool {
	ch1 := make(chan int)
	go Walk(t1, ch1)

	ch2 := make(chan int)
	go Walk(t2, ch2)

	for {
		n1, ok1 := <-ch1
		n2, ok2 := <-ch2

		if !ok1 && !ok2 {
			return true
		}
		
		if ok1 != ok2 || n1 != n2 {
			return false
		}
	}

	return true
}

func main() {
	t1a := tree.New(1)
	fmt.Println(t1a)
	
	t1b := tree.New(1)
	fmt.Println(t1b)
	
	t2 := tree.New(2)
	fmt.Println(t2)
	
	fmt.Println("t1a == t1b:", Same(t1a, t1b))
	fmt.Println("t1a == t2:", Same(t1a, t2))
}