和为S的两个数字

 1 class Solution {
 2 public:
 3     vector<int> FindNumbersWithSum(vector<int> array,int sum) {
 4         vector<int> vv;
 5         int len = array.size();
 6         if (len < 2)
 7             return vv;
 8         map<int,int> mm;
 9         for (int i = 0;i < len ; ++i)
10         {
11             if(mm.count(array[i]) == 0)
12             {
13                 mm[array[i]] = 1;
14             }
15             else
16             {
17                 ++mm[array[i]];
18             }
19         }
20         int i = 0;
21         bool have = 0;
22         for (;i < len/2 + 1 ; ++i)
23         {
24             --mm[array[i]];
25             if(mm.count(sum - array[i]) > 0 && mm[sum - array[i]] > 0)
26             {
27                 have = 1;
28                 break;
29             }
30             ++mm[array[i]];
31         }
32         if(!have)
33             return vv;
34         
35         vv.push_back(array[i]);
36         vv.push_back(sum - array[i]);
37         return vv;
38     }
39 };