From 22a960052265d8a92e9044cbb048d5316dc2d216 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: Sat, 3 Nov 2018 14:25:40 +0800
Subject: [PATCH] Create 112. Path Sum.md

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+# [112. Path Sum](https://leetcode.com/problems/path-sum/description/)
+# 思路
+根据题意，若树空则肯定是false，若非空，则:
+* 若没有左右子树（叶子），判断其值是否满足条件；
+* 否则，递归判断其左右子树是否满足，只要有一个满足即满足(即或操作)。
+
+# C++
+``` C++
+class Solution {
+public:
+    bool hasPathSum(TreeNode* root, int sum) {
+        if(root == NULL) return false;
+        if(root -> left == NULL && root -> right == NULL && sum == (root -> val)) return true; // 叶子节点
+        return hasPathSum(root -> left, sum - (root -> val)) || hasPathSum(root -> right, sum - (root -> val));
+    }
+};
+```