stl map3

#include <stdio.h>
#include <iostream>
#include <map>
#include <algorithm>

using namespace std;

int main( )
{
    //用insert函数插入value_type 数据
    map<int,string>stu;
    int n, i;
    stu.insert(map<int,string>::value_type(1,"bcdefg"));
    stu.insert(map<int,string>::value_type(4,"abcdef"));
    stu.insert(map<int,string>::value_type(2,"efghfg"));
    map<int,string>::iterator iter;
    n = stu.size( );
    //map的遍历 应用前向迭代器
    for ( iter = stu.begin( ); iter != stu.end( ); iter++)
        cout<<iter->first<<"  "<<iter->second<<endl;
    //map的大小
    cout<<n<<endl;
    //map的遍历 应用反向迭代器
    map<int,string>::reverse_iterator it;
    for ( it = stu.rbegin( ); it != stu.rend( ); it++)
        cout<<it->first<<" "<<it->second<<endl;
    puts("");
    return 0;
}