1 #include "stdafx.h"
 2 #include "vector"
 3 #include "map"
 4 #include "iostream"
 5 #include "unordered_map"        //unordered_map的头文件
 6 using namespace std;
 7
 8 class MyClass
 9 {
10 public:
11     vector<vector<int> > twoSum(vector<int> &nums, int target)
12     {
13         unordered_map<int, int> hash;        //初始化名为hash的hash table,<key,value>均为int型
14         int size = nums.size();
15         vector<vector<int> > res;            //先定义一个vector<vector<int> > 存放所有符合条件的组合
16         vector<int> inIt;                    //存放每一个符合条件的组合
17         int j = 0;
18         for (int i = 0; i < size; i++)
19         {
20             int numToFind = target - nums[i];
21             if (hash.find(numToFind) != hash.end())
22             {
23                 inIt.push_back(hash[numToFind]);        //先将每组的数放入到inIt中
24                   inIt.push_back(i);
25                 res.push_back(inIt);                    //将这个组放入到res中
26                 inIt.clear();                            //清除每组的值
27             }
28             hash[nums[i]] = i;                            //将vector中的值放到map中
29         }
30         return res;
31     }
32 };
33
34 int _tmain(int argc, _TCHAR* argv[])
35 {
36     vector<int> nums = { 1, 2, 3, 4, 4, 9, 8, 10 };
37     int target = 5;
38     vector<vector<int> > res;
39     MyClass solution;
40     res = solution.twoSum(nums, target);
41     int size = res.size();
42     for (int i = 0; i < size; i++)
43     {
44         int vsize = res[i].size();
45         cout << "[";
46         for (int j = 0; j < vsize; j++)
47         {
48             cout << res[i][j] << " ";
49         }
50         cout << "]";
51     }
52     cout << endl;
53     system("pause");
54     return 0;
55 }