unorder_map 自定义KEY

1. boost::unorder_map 实现自定义KEY

 // boostLibTest.cpp : 定义控制台应用程序的入口点。
 //
 #include "stdafx.h"

 #include <boost/functional/hash.hpp>
 #include <boost/unordered_map.hpp>
 #include <iostream>
 #include <set>
 #include <map>
 #include <unordered_map>

 using namespace std;

     struct Test
     {
         int _id;
         string _name;
         set<int> _nums;

         Test(int id, string name, set<int> nums = set<int>()) :
             _id(id), _name(name), _nums(nums)
         {
         }
     };

     bool operator==(const Test& ts1, const Test& ts2)
     {
         return ts1._id == ts2._id && ts1._name == ts2._name && ts1._nums == ts2._nums;
     }

     size_t hash_value(const Test& test)
     {
         std::size_t seed = ;
         boost::hash_combine(seed, std::hash_value(test._id));
         boost::hash_combine(seed, std::hash_value(test._name));
         for (auto& iter : test._nums){
             boost::hash_combine(seed, std::hash_value(iter));
         }
         return seed;
     }

 int _tmain(int argc, _TCHAR* argv[])
 {
     set<int> sets = {,,,,};
     boost::unordered_map<Test, string> map;
     map.insert(make_pair(Test(, "abc", sets), ""));
     map.insert(make_pair(Test(, "def", sets), ""));
     map.insert(make_pair(Test(, "egh", sets), ""));
     map.insert(make_pair(Test(, "ijk", sets), ""));
     map.insert(make_pair(Test(, "lmn", sets), ""));

     auto iter = map.find(Test(, "egh", sets));
     if (iter != map.end()){
         cout << "Find !" << endl;
     }
     else{
         cout << "Not Find !" << endl;
     }

     getchar();
     return ;
 }

输出结果为： Find !

===============================================================

2. std::unorder_map 实现自定义KEY

 // boostLibTest.cpp : 定义控制台应用程序的入口点。
 //
 #include "stdafx.h"

 #include <boost/functional/hash.hpp>
 #include <boost/unordered_map.hpp>
 #include <iostream>
 #include <set>
 #include <map>
 #include <unordered_map>

 using namespace std;

     struct Test
     {
         int _id;
         string _name;
         set<int> _nums;

         Test(int id, string name, set<int> nums = set<int>()) :
             _id(id), _name(name), _nums(nums)
         {
         }
     };

     namespace std
     {
         template<>
         struct hash<Test>
             : public _Bitwise_hash < Test >
         {   // hash functor for RECT
         };

         inline bool operator == (const Test &ts1, const Test &ts2) _NOEXCEPT
         {
             return ts1._id == ts2._id && ts1._name == ts2._name && ts1._nums == ts2._nums;
         }
     }

 int _tmain(int argc, _TCHAR* argv[])
 {
     set<int> sets = {,,,,};
     std::unordered_map<Test, string> map;
     map.insert(make_pair(Test(, "abc", sets), ""));
     map.insert(make_pair(Test(, "def", sets), ""));
     map.insert(make_pair(Test(, "egh", sets), ""));
     map.insert(make_pair(Test(, "ijk", sets), ""));
     map.insert(make_pair(Test(, "lmn", sets), ""));

     auto iter = map.find(Test(, "egh", sets));
     if (iter != map.end()){
         cout << "Find !" << endl;
     }
     else{
         cout << "Not Find !" << endl;
     }

     getchar();
     return ;
 }

奇怪的地方来了，std的结果有时候是 Find ！ 有时候是 Not Find ！

没弄明白这个std::unorder_map怎么回事，我自己直接用了boost::unorder_map