binary_tree_with_goroutine.go

// Walk walks the tree t sending all values
// from the tree to the channel ch.
func Walk(t *tree.Tree, ch chan int) {
    recursiveWalk(t, ch)
    close(ch) // close channel when done
}

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

// Same determines whether the trees
// t1 and t2 contain the same values.
func Same(t1, t2 *tree.Tree) bool {
    // create channels to message pass
    ch1 := make(chan int)
    ch2 := make(chan int)
    // create goroutines with channels
    go Walk(t1, ch1)
    go Walk(t2, ch2)

    for {
        // receive message from channels concurrently
        v1, ok1 := <-ch1
        v2, ok2 := <-ch2
        // something in the tree isn't the same
        if v1 != v2 || ok1 != ok2 {
            return false
        }
        // got to end with everything equal
        if !ok1 {
            break
        }
    }
    return true
}