📝 docs : add 872. Leaf-Similar Trees.md

Author: GoogTech

docs/LeetCod刷题之旅及题目解析/872.叶子相似的树/872.叶子相似的树.md

@@ -0,0 +1,107 @@
+## 872. 叶子相似的树
+> https://leetcode-cn.com/problems/leaf-similar-trees/
+
+
+### Java
+```java
+/*
+ * @Author: Goog Tech
+ * @Date: 2020-08-16 17:27:08
+ * @LastEditTime: 2020-08-16 17:47:02
+ * @Description: https://leetcode-cn.com/problems/leaf-similar-trees/
+ * @FilePath: \leetcode-googtech\#872. Leaf-Similar Trees\Solution.java
+ * @WebSite: https://algorithm.show/
+ */
+
+/*
+ * @lc app=leetcode.cn id=872 lang=java
+ *
+ * [872] 叶子相似的树
+ */
+
+// @lc code=start
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+
+    // DFS: 深度优先搜索
+    public boolean leafSimilar(TreeNode root1, TreeNode root2) {
+        // 判断两个二叉树的叶值序列是否相同
+        String leftLeaf = dfs(root1, "");
+        String rightLeaf = dfs(root2, "");
+        return leftLeaf.equals(rightLeaf);
+    }
+
+    private String dfs(TreeNode root, String result) {
+        // 判断当前节点是否为空
+        if(root == null) return result;
+        // 判断当前节点是否为叶子节点,若是则对其进行拼接
+        if(root.left == null && root.right == null) {
+            // 添加分隔符的目的: https://leetcode-cn.com/problems/leaf-similar-trees/comments/548544
+            result += '-'; 
+            result += result + root.val;
+            return result;
+        }
+        // 递归遍历当前节点的左右孩子节点
+        return dfs(root.left, result) + dfs(root.right, result);
+    }
+}
+// @lc code=end
+```
+
+### Python
+```python
+'''
+Author: Goog Tech
+Date: 2020-08-16 17:28:02
+LastEditTime: 2020-08-16 17:39:45
+Description: https://leetcode-cn.com/problems/leaf-similar-trees/
+FilePath: \leetcode-googtech\#872. Leaf-Similar Trees\Solution.py
+WebSite: https://algorithm.show/
+'''
+
+#
+# @lc app=leetcode.cn id=872 lang=python
+#
+# [872] 叶子相似的树
+#
+
+# @lc code=start
+# Definition for a binary tree node.
+# class TreeNode(object):
+#     def __init__(self, x):
+#         self.val = x
+#         self.left = None
+#         self.right = None
+
+class Solution(object):
+
+    # 先序遍历
+    def leafSimilar(self, root1, root2):
+        """
+        :type root1: TreeNode
+        :type root2: TreeNode
+        :rtype: bool
+        """
+        # 用于存储两个二叉树的叶子节点
+        nums1, nums2 = [], []
+        def leaf(root, nums):
+            # 判断当前节点是否为空并且是否为叶子节点,若是则将其添加到nums中
+            if root and not root.left and not root.right:
+                nums.append(root.val)
+            # 递归遍历当前节点的左右孩子节点
+            if root.left: leaf(root.left, nums)
+            if root.right: leaf(root.right, nums)
+            # 返回叶子节点列表
+            return nums
+        # 判断两个二叉树的叶值序列是否相同
+        return leaf(root1, nums1) == leaf(root2, nums2)
+# @lc code=end
+```

docs/SUMMARY.md

@@ -80,6 +80,7 @@
     * [680.验证回文字符串Ⅱ](LeetCod刷题之旅及题目解析/680.验证回文字符串Ⅱ/680.验证回文字符串Ⅱ.md)
     * [700.二叉搜索树中的搜索](LeetCod刷题之旅及题目解析/700.二叉搜索树中的搜索/700.二叉搜索树中的搜索.md)
     * [709.转换成小写字母](LeetCod刷题之旅及题目解析/709.转换成小写字母/709.转换成小写字母.md)
+    * [872.叶子相似的树](LeetCod刷题之旅及题目解析/872.叶子相似的树/872.叶子相似的树.md)
     * [876.链表的中间结点](LeetCod刷题之旅及题目解析/876.链表的中间结点/876.链表的中间结点.md)
     * [905.按奇偶排序数组](LeetCod刷题之旅及题目解析/905.按奇偶排序数组/905.按奇偶排序数组.md)
     * [938.二叉搜索树的范围和](LeetCod刷题之旅及题目解析/938.二叉搜索树的范围和/938.二叉搜索树的范围和.md)