二维map遍历

#include <iostream>
#include <cstdio>
#include <map>
using namespace std;

map<int,map<int,int> > mp;
int main()
{
   mp[0][0]=1;
   mp[0][1]=2;
   mp[1][0]=3;

   for(map<int,map<int,int> >::iterator it = mp.begin();it!=mp.end();it++)
   {
       for(map<int,int>:: iterator it2 = (it->second).begin();it2!=(it->second).end();it2++)
       {
           cout<<it2->second<<" ";
       }
       cout<<endl;
   }
    return 0;
}