STL map内map

#include "stdafx.h"

#include <string>

#include <iostream>

#include <map>

#include <list>

using namespace std;

 

#if defined (_MSC_VER)

#pragma warning(disable: 4786)

#endif

struct Node

{

         int m_id;

         stringm_str;

         bool operator<(Node const& _A) const

         {

                   //排序策略,首先按m_id排序,m_id相等则按m_str排序

                   return m_id < _A.m_id ? true:(m_id>_A.m_id ? false : m_str.compare(_A.m_str)<0);

         }

         Node(int id,stringstr)

         {

                   m_id=id;

                   m_str=str;

         }

         Node(){}

};

int main(int argc, char* argv[])

{

         map<int,Node> mapNode,mapNode2;

         typedef pair<int,Node> Painr1;

         mapNode.insert(Painr1(1,Node(1,"str1")));

         mapNode2.insert(Painr1(1,Node(1,"str2")));

 

         map< int, map<int,Node>* >mapList;

         typedef pair< int, map<int,Node> *> Painr2;

         mapList.insert(Painr2(1,&mapNode));

         mapList.insert(Painr2(2,&mapNode2));

 

         map< int, map<int,Node>* >::iterator itemFirst;

         map< int, Node>* pNode=NULL;//应该为指针不是迭代器

         map< int, Node>::iterator itemSecond;

 

         for(itemFirst=mapList.begin();itemFirst!=mapList.end();++itemFirst)//第一层

         {

                   pNode=itemFirst->second;

                   for (itemSecond=pNode->begin();itemSecond!=pNode->end();++itemSecond)//第二层

                   {

                            cout<<itemSecond->first<<endl;

                            cout<<itemSecond->second.m_str<<endl;

                   }

         }

         return 0;

}