c++ map

#include<iostream>
#include <vector>
#include<map>

using std::vector;
using std::cin;
using std::cout;
using std::endl;
using std::string;
using std::pair;
using std::map;

typedef pair<int, string> Author;
int playPair() {

 Author a1(1, "david");

 cout << a1.first << "  " << a1.second << endl;
 return 0;
}

void playMap() {
 typedef map<int, string> address;
 Author a1(2, "david");
 Author a2(3, "ccde");
 address mapAddress;

 

 //add element
 mapAddress.insert(a1);
 mapAddress.insert(a2);
 mapAddress.insert(address::value_type(4, "df43234"));

 

 //use iterator

 map<int, string>::iterator iter;

 

 //get element by key
 iter = mapAddress.find(2);
 cout << iter->first << " the first key of 2" << endl;

 //遍历map
 for (iter = mapAddress.begin(); iter != mapAddress.end();
   iter.operator ++()) {

  cout << "| " << iter->first << " | " << iter->second << endl;

 }

 

 //delete element
 iter = mapAddress.find(2);
 mapAddress.erase(iter);
 cout << "after erase" << endl;

 

 for (iter = mapAddress.begin(); iter != mapAddress.end();
   iter.operator ++()) {
  cout << "| " << iter->first << " | " << iter->second << endl;
 }

}