From 2e1db50ece93c107ba70fb6dfbd474f657c2be78 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, 1 Sep 2018 21:30:37 +0800
Subject: [PATCH] Create 66. Plus One.md

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 create mode 100644 66. Plus One.md

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+# [66. Plus One](https://leetcode.com/problems/plus-one/description/)
+# 思路
+首先明确英语中digit代表0-9的一个数字。这题意思就是用一个数组代表一个数，然后计算这个数加1后的结果。  
+从后往前遍历，用一个c记录每一个digit所加的数，初试为1，以后每个c为前一次加法的进位。  
+注意如果最后有进位的话会使数组size加1
+# C++
+```
+class Solution {
+public:
+    vector<int> plusOne(vector<int>& digits) {
+        int i = digits.size()-1;
+        int c = 1;
+        while(i >= 0){
+            digits[i] += c;
+            c = digits[i] / 10;
+            digits[i] %= 10;
+            i--;
+        }
+        if(c > 0) digits.insert(digits.begin(), c);
+        return digits;
+    }
+};
+```