002.Plus One

Given a non-negative number represented as an array of digits, plus one to the number.

1. 数字 正序排列

6789= 6 7 8 9；

2.反序 计算，判断进位

 9 8 7 6 +1

0 9 7 6

3.反序排列

 class Solution {
 public:
     vector<int> plusOne(vector<int> &digits) {
         // Start typing your C/C++ solution below
         // DO NOT write int main() function
         vector<int> v;

         int next = 1;
         for(int i = digits.size() - 1; i >= 0 ; i--)
         {
             int tmp = digits[i] + next;
             v.push_back(tmp%10);
             next = tmp/10;
         }

         if(next != 0)
         {
             v.push_back(next);
         }

         for(int i = 0; i < v.size()/2; i++)
         {
             int t = v[i];
             v[i] = v[v.size() - 1 - i];
             v[v.size() - 1 - i] = t;
         }
         return v;
     }
 };