Equivalent Binary Trees

eqbintree.go

package main

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

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

// Returns channel for reading only
func Walker(t *tree.Tree, printed bool) <-chan int {
	ch := make(chan int)
	go func() {
		Walk(t, ch)
		close(ch)
	}()
	if (printed) {
		for i := range ch {
			fmt.Println(i)
		}
	}
	return ch
}

// Same determines whether the trees
// t1 and t2 contain the same values.
func Same(t1, t2 *tree.Tree) bool {
	c1, c2 := Walker(t1, false), Walker(t2, false)
	for {
		v1, ok1 := <-c1
		v2, ok2 := <-c2
		if !ok1 || !ok2 {
			return ok1 == ok2
		}
		if v1 != v2 {
			break
		}
	}
	return false
}

func main() {
	t := tree.New(1)
	fmt.Printf("%T %v\n", t, t)

	Walker(t, true)

	test1, test2 := Same(tree.New(1), tree.New(1)), Same(tree.New(1), tree.New(2))
	fmt.Println(test1, test2)
}