From 27f86de1337423e77a11a8d2030d392394820463 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=94=90=E6=A0=91=E6=A3=AE?= <14021051@buaa.edu.cn>
Date: Wed, 31 Oct 2018 21:03:51 +0800
Subject: [PATCH] Create 100. Same Tree.md

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 create mode 100644 100. Same Tree.md

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+# [100. Same Tree](https://leetcode.com/problems/same-tree/description/)
+# 思路
+判断两棵树是否完全相同。最简单的思路就是递归算法，两棵树非空树完全相同的充要条件是:
+* 根的值相同;
+* 且左子树和右子树都是分别完全相同的。
+
+当然也可以考虑遍历两棵树直到遇到不相同的节点即可返回false，若同时遍历完则返回true。
+
+# C++
+``` C++
+class Solution {
+public:
+    bool isSameTree(TreeNode* p, TreeNode* q) {
+        if(p == NULL && q==NULL) return true;  // 都是空树
+        if(p == NULL || q == NULL || (p -> val != q -> val)) return false;
+        return isSameTree(p -> left, q -> left) && isSameTree(p -> right, q -> right);
+    }
+};
+```