C++标准模板库map的常用操作

  map<int, string> map1;
  //方法1：
  map1.insert(pair<int, string>(2, \"beijing\"));
  //方法2:
  map1[4] = \"changping\";
  //方法3:
  map1.insert(map<int, string>::value_type(1, \"huilongguan\"));
  //方法4:
  map1.insert(make_pair<int, string>(3, \"xierqi\"));

for (map<int, string>::iterator it=map1.begin(); it!=map1.end(); it++)
 {
 cout << it->first << \":\" << it->second << endl;
 }

 string value1 = map1[2];
 if (value1.empty())
 {
 cout << \"not found\" << endl;
 }
 //方法2
 map<int, string>::iterator it = map1.find(2);
 if (it == map1.end())
 {
 cout << \"not found\" << endl;
 }
 else
 {
 cout << it->first << \":\" << it->second << endl;
 }

 //修改数据
 map1[2] = \"tianjin\";

 //方法1
 map1.erase(1);
 //方法2
 map<int, string>::iterator it1 = map1.find(2);
 map1.erase(it1);