Exercise: Equivalent Binary Trees

main.go

package main

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

func Walk(t *tree.Tree, ch chan int) {
	WalkSub(t, ch)
	close(ch)
}

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

// Same determines whether the trees
// t1 and t2 contain the same values.
func Same(t1, t2 *tree.Tree) bool {
	c1 := make(chan int)
	c2 := make(chan int)
	go Walk(t1, c1)
	go Walk(t2, c2)
	ar1 := flatTree(t1, c1)
	ar2 := flatTree(t2, c2)
	for i, x := range ar1 {
		if ar2[i] != x {
			return false
		}
	}
	return true
}

func flatTree(t *tree.Tree, c chan int) []int {
	a := []int{}
	for x := range c {
		a = append(a, x)
	}
	sort.Ints(a)
	return a
}

func main() {
	t1 := tree.New(2)
	t2 := tree.New(2)
	fmt.Println(Same(t1, t2))
}