1022 Digital Library （30 分）

#include<iostream>
#include<stdio.h>
#include<stdlib.h>
#include<string>
#include<map>
using namespace std;

map<string, set<string>> mpTitle, mpAuthor, mpKey, mpPub, mpYear;

void query(int n, string & info)
{
    if (n == 1)
    {
        if (!mpTitle[info].empty())
        {
            for (string s : mpTitle[info]) cout << s << endl;
        }
        else cout << "Not Found\n";
    }
    else if (n == 2)
    {
        if (!mpAuthor[info].empty())
        {
            for (string s : mpAuthor[info]) cout << s << endl;
        }
        else cout << "Not Found\n";
    }
    else if (n == 3)
    {
        if (!mpKey[info].empty())
        {
            for (string s : mpKey[info]) cout << s << endl;
        }
        else cout << "Not Found\n";
    }
    else if (n == 4)
    {
        if (!mpPub[info].empty())
        {
            for (string s : mpPub[info]) cout << s << endl;
        }
        else cout << "Not Found\n";
    }
    else if (n == 5)
    {
        if (!mpYear[info].empty())
        {
            for (string s : mpYear[info]) cout << s << endl;
        }
        else cout << "Not Found\n";
    }
}
int main()  
{
    int n;
    string id, title, author, key, pub, year;
    scanf("%d", &n);
    getchar();
    for (int i = 0; i < n; i++)
    {
        getline(cin, id);//从缓冲区读取字符直至遇到'\n'，随后提取并丢弃'\n'
        getline(cin, title);
        mpTitle[title].insert(id);
        getline(cin, author);
        mpAuthor[author].insert(id);
        while (cin >> key)
        {
            mpKey[key].insert(id);
            char c = getchar();
            if (c == '\n') break;
        }
        getline(cin, pub);
        mpPub[pub].insert(id);
        getline(cin, year);
        mpYear[year].insert(id);
    }
    scanf("%d", &n);
    for (int i = 0; i < n; i++)
    {
        int queryid;
        scanf("%d: ", &queryid);
        string queryinfo;
        getline(cin, queryinfo);
        cout << queryid << ": " << queryinfo << endl;
        query(queryid, queryinfo);
    }
    system("pause");
    return 0;
}