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September 5, 2013 16:07
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A Tour of Go - Exercise: Equivalent Binary Trees
http://tour.golang.org/#70
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package main | |
import "code.google.com/p/go-tour/tree" | |
import "fmt" | |
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) | |
} | |
} | |
// Walk walks the tree t sending all values | |
// from the tree to the channel ch. | |
func Walk(t *tree.Tree, ch chan int) { | |
_walk(t, ch) | |
close(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) | |
for { | |
val1, ok1 := <- c1 | |
val2, ok2 := <- c2 | |
if !ok1 || !ok2 { // one of them finished | |
if ok1 != ok2 { // they didn't finished at the same time | |
return false | |
} | |
break | |
} | |
if val1 != val2 { | |
return false | |
} | |
} | |
return true | |
} | |
func main() { | |
k := 1 | |
ch := make(chan int) | |
tr := tree.New(k) | |
go Walk(tr, ch) | |
for i:=0; i < 10; i++ { | |
fmt.Println(<-ch) | |
} | |
fmt.Println(Same(tree.New(1), tree.New(1))) | |
fmt.Println(Same(tree.New(1), tree.New(2))) | |
} |
package main
import (
"golang.org/x/tour/tree"
"fmt"
)
func Walk(t *tree.Tree, ch chan int) {
if t == nil {
return
}
Walk(t.Left, ch)
ch <- t.Value
Walk(t.Right, ch)
}
func Same(t1, t2 *tree.Tree) bool {
// Way 2 :
//return fmt.Sprintf("%v", *t1) == fmt.Sprintf("%v", *t2)
// Way 1 -- START
ch1 := make(chan int)
ch2 := make(chan int)
go Walk(t1, ch1)
go Walk(t2, ch2)
if <-ch1 != <-ch2 {
close(ch1)
close(ch2)
return false
}
return true
// Way 1 -- END
}
func main() {
//fmt.Println(Same(tree.New(1), tree.New(1))) // true
t1 := tree.New(1)
t2 := tree.New(2)
fmt.Println(t1, "\n", t2)
fmt.Println(Same(t1, t2)) // false
}
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