From 0ab039ab954fb125459b5dcc901995f64f59137b 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: Thu, 13 Sep 2018 12:37:33 +0800
Subject: [PATCH] Create 202. Happy Number.md

---
 202. Happy Number.md | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 202. Happy Number.md

diff --git a/202. Happy Number.md b/202. Happy Number.md
new file mode 100644
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+++ b/202. Happy Number.md	
@@ -0,0 +1,28 @@
+# [202. Happy Number](https://leetcode.com/problems/happy-number/description/)
+# 思路
+按照题目的意思进行循环，判断每次循环结果是否为1，若是则返回true，否则用map记录结果，然后修改n进行下一次循环。  
+# C++
+```
+class Solution {
+private:
+    int count_sum(int n){ // 定义题目中所述的求和函数
+        int sum = 0;
+        while(n > 0){
+            sum += (n % 10) * (n % 10);
+            n /= 10;
+        }
+        return sum;
+    }
+public:
+    bool isHappy(int n) {
+        map<int, int>mp;
+        while(n){
+            if(n == 1) return true;
+            if(mp[n] == 1) return false;
+            mp[n] = 1;
+            n = count_sum(n);
+        }
+        return false;
+    }
+};
+```