#include <iostream>
#include <fstream>
#include <string>
#include <map>
#include <cmath>
using namespace std;
struct node{
int item;
int rating;
};
void main()
{
multimap<int,node>os;
ifstream data("data1.txt");
int user;
char fenhao='::';
while(data>>user>>fenhao>>node.item>>fenhao>>node.rating)
data.close();data.clear();
data.open("data2.txt");
multimap<int,node>::const_iterator iter=os.begin();
ofstream data1("data.txt");
int i=0;
while(iter!=os.end())
{
data1<<(*iter).first<<":"<<(*iter).second<<" ";
data1<<endl;
++iter;
}
data1.close();data1.clear();
}
这个定义写法有什么错误吗