LeetCode --- Two Sum

 1 #include <vector>
 2 #include <iostream>
 3 #include <algorithm>
 4 using namespace std;
 5 
 6 class Solution {
 7 public:
 8     vector<int> twoSum(vector<int> &numbers, int target) {
 9         typedef pair<int, int> pii;
10         vector<pii> my_pair;
11         for (unsigned int i = 0; i < numbers.size(); i++) {
12             my_pair.push_back(pii(numbers[i], i+1));
13         }
14         sort(my_pair.begin(), my_pair.end());
15         vector <int> ans;
16         unsigned int beg = 0, end = numbers.size() - 1;
17         while (beg < end) {
18             if (my_pair[beg].first + my_pair[end].first == target) {
19                 ans.push_back(my_pair[beg].second);
20                 ans.push_back(my_pair[end].second);
21                 break;
22             }
23             else if (my_pair[beg].first + my_pair[end].first > target) {
24                 end--;
25             }
26             else if (my_pair[beg].first + my_pair[end].first < target) {
27                 beg++;
28             }
29          }
30          if (ans[0] > ans[1])
31             swap(ans[0], ans[1]);
32          return ans;
33     }
34 };