package main

import (
	"fmt"

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

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

// walk traverses the tree by the pre-order
func walk(t *tree.Tree, ch chan int) {
	if t != nil {
		ch <- t.Value

		walk(t.Left, ch)

		walk(t.Right, ch)
	}

}

func Same(t1, t2 *tree.Tree) bool {

	ch1 := make(chan int)
	ch2 := make(chan int)

	go Walk(t1, ch1)
	go Walk(t2, ch2)

	x, y := 0, 0
	ok := true
	for {
		select {
		case x, ok = <-ch1:
			if !ok {
				return true
			}
			y = <-ch2
			if x != y {
				return false
			}

		case x, ok = <-ch2:
			if !ok {
				fmt.Println("ch2 done")
				fmt.Println(x)
				return true
			}
			fmt.Println("ch2")
			fmt.Println(x)
			y = <-ch1
			fmt.Println("ch1")
			fmt.Println(y)
			if x != y {
				return false
			}
		}
	}

	return true
}

func main() {

	// fmt.Println(Same(tree.New(1), tree.New(1)))

	t := tree.New(1)
	fmt.Println(Same(t, t))

	// fmt.Println(Same(tree.New(1), tree.New(2)))
}