g0601_0700.s0606_construct_string_from_binary_tree

Class Solution

java.lang.Object

g0601_0700.s0606_construct_string_from_binary_tree.Solution

public class Solution
extends Object

606 - Construct String from Binary Tree.

Easy

Given the root of a binary tree, construct a string consisting of parenthesis and integers from a binary tree with the preorder traversal way, and return it.

Omit all the empty parenthesis pairs that do not affect the one-to-one mapping relationship between the string and the original binary tree.

Example 1:

Input: root = [1,2,3,4]

Output: “1(2(4))(3)”

Explanation: Originally, it needs to be “1(2(4)())(3()())”, but you need to omit all the unnecessary empty parenthesis pairs. And it will be “1(2(4))(3)”

Example 2:

Input: root = [1,2,3,null,4]

Output: “1(2()(4))(3)”

Explanation: Almost the same as the first example, except we cannot omit the first parenthesis pair to break the one-to-one mapping relationship between the input and the output.

Constraints:

• The number of nodes in the tree is in the range [1, 104].
• -1000 <= Node.val <= 1000

Constructor Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
String	tree2str(TreeNode t)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

tree2str

public String tree2str(TreeNode t)