题目:
题解:
Go
type Codec struct{}
func Constructor() (_ Codec) {
return
}
func (c Codec) serialize(root *TreeNode) string {
if root == nil {
return "X"
}
left := "(" + c.serialize(root.Left) + ")"
right := "(" + c.serialize(root.Right) + ")"
return left + strconv.Itoa(root.Val) + right
}
func (Codec) deserialize(data string) *TreeNode {
var parse func() *TreeNode
parse = func() *TreeNode {
if data[0] == 'X' {
data = data[1:]
return nil
}
node := &TreeNode{}
data = data[1:] // 跳过左括号
node.Left = parse()
data = data[1:] // 跳过右括号
i := 0
for data[i] == '-' || '0' <= data[i] && data[i] <= '9' {
i++
}
node.Val, _ = strconv.Atoi(data[:i])
data = data[i:]
data = data[1:] // 跳过左括号
node.Right = parse()
data = data[1:] // 跳过右括号
return node
}
return parse()
}