tour_go_72.go

package main

import (
	"code.google.com/p/go-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.Left != nil {
		Walk(t.Left, ch)
	}
    ch <- t.Value
	if t.Right != nil {
		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)
    ch2 := make(chan int)
    go Walk(t1, ch1)
    go Walk(t2, ch2)

    for i := 0; i < 10; i++ {
        if <-ch1 != <-ch2 {
        	return false
        }
    }
    return true
}

func main() {
	ch := make(chan int)
	go Walk(tree.New(1), ch)
	for i := 0; i < 10; i++ {
		n := <-ch
		fmt.Println(n)
	}

    if Same(tree.New(1), tree.New(1)) {
        fmt.Println("all good");
    }


    if Same(tree.New(1), tree.New(2)) {
        fmt.Println("shouldn't happen");
    }
}