No.66 Plus One

 1 #include "stdafx.h"
 2 #include <map>
 3 #include <vector>
 4 #include <iostream>
 5 using namespace std;
 6 
 7 class Solution
 8 {
 9 public:
10     vector<int> plusOne(vector<int> &digits)
11     {//给定一个数组表示的非负数，实现该数加1
12         int carry = 0;//保存进位
13         int size = digits.size();
14         vector<int> res;
15         if(size == 0)
16         { 
17             res.push_back(1);
18             return res;
19         }
20         res = digits;
21         for(int i=size-1; i>=0 ; i--)//从后向前加
22         {
23             if(i == size-1)
24             {
25                 res[i] = (digits[i]+1)%10;
26                 carry = (digits[i]+1)/10;
27             }
28             if(carry == 0)
29                 break;
30             else
31             {
32                 res[i] = (digits[i]+carry)%10;
33                 carry = (digits[i]+carry)/10;
34             }
35         }
36         if(carry!=0)
37             res.insert(res.begin(),carry);
38         
39         return res;
40     }
41 };
42 
43 int main()
44 {
45     Solution sol;
46     int data[] = {9,9,8,4,2};
47     vector<int> test(data,data+sizeof(data)/sizeof(int));
48     vector<int> res;
49     for(const auto &i : test)
50         cout << i << " ";
51     cout << endl;
52     res = sol.plusOne(test);
53     for(const auto &i : res)
54         cout << i << " ";
55     cout << endl;    
56 }