A Tour of Go Exercise: Equivalent Binary Trees https://tour.golang.org/concurrency/8

exercise-equivalent-binary-trees.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) {
	if t == nil {
		return
	}
	WalkImpl(t, ch)
	close(ch)
}

func WalkImpl(t *tree.Tree, ch chan int) {
	if t.Left != nil {
		WalkImpl(t.Left, ch)
	}
	ch <- t.Value
	if t.Right != nil {
		WalkImpl(t.Right, ch)
	}
}

// Same determines whether the trees
// t1 and t2 contain the same values.
func Same(t1, t2 *tree.Tree) bool {
	ch1, ch2 := make(chan int), make(chan int)
	go Walk(t1, ch1)
	go Walk(t2, ch2)
	var a1, a2 []int
	for n := range ch1 {
		a1 = append(a1, n)
	}
	for n := range ch2 {
		a2 = append(a2, n)
	}
	if len(a1) != len(a2) {
	return false
	}
	for i := range a1 {
		if a1[i] != a2[i] {
			return false
		}
	}
	return true
}

func checkWalk(n int) {
	ch := make(chan int)
	t := tree.New(n)
	fmt.Printf("%v\n", t)
	go Walk(t, ch)
	for n := range ch {
		fmt.Printf("%d\n", n)
	}
}

func checkSame(n int) {
	t1, t2 := tree.New(n), tree.New(n)
	fmt.Printf("%v\n", t1)
	fmt.Printf("%v\n", t2)
	fmt.Print(Same(t1, t2))
}

func main() {
	// checkWalk(1)
	checkSame(2)
}