[PAT-A] 1022 Digital Library

Java

import java.util.*;
import java.io.*;

/**
 * 测试点4概率超时
 */
public class Main {
    static class Book {
        String id, name, author;
        Set<String> keywords;
        String publisher, year;

        Book(String id, String name, String author, Set<String> keywords, String publisher, String year) {
            this.id = id;
            this.name = name;
            this.author = author;
            this.keywords = keywords;
            this.publisher = publisher;
            this.year = year;
        }
    }

    public static void main(String[] args) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        int n = Integer.parseInt(reader.readLine());

        List<Book> books = new ArrayList<>();
        for (int i = 0; i < n; i++) {
            String id = reader.readLine();
            String name = reader.readLine();
            String author = reader.readLine();

            String line = reader.readLine();
            Set<String> keywords = new HashSet<>(Arrays.asList(line.split(" ")));

            String publisher = reader.readLine();
            String year = reader.readLine();

            books.add(new Book(id, name, author, keywords, publisher, year));
        }

        int m = Integer.parseInt(reader.readLine());
        String line;
        while (m-- > 0) {
            line = reader.readLine();
            System.out.println(line);
            String info = line.substring(3);
            char t = line.charAt(0);
            List<String> res = new ArrayList<>();

            for (Book book : books) {
                switch (t) {
                    case '1':
                        if (book.name.equals(info)) res.add(book.id);
                        break;
                    case '2':
                        if (book.author.equals(info)) res.add(book.id);
                        break;
                    case '3':
                        if (book.keywords.contains(info)) res.add(book.id);
                        break;
                    case '4':
                        if (book.publisher.equals(info)) res.add(book.id);
                        break;
                    case '5':
                        if (book.year.equals(info)) res.add(book.id);
                        break;
                }
            }

            if (res.isEmpty()) System.out.println("Not Found");
            else {
                Collections.sort(res);
                for (String id : res) System.out.println(id);
            }
        }
    }
}

C++

#include <iostream>
#include <cstring>
#include <algorithm>
#include <set>
#include <vector>
#include <sstream>

using namespace std;

struct Book {
    string id, name, author;
    set <string> keywords;
    string publisher, year;
};

int main() {
    int n, m;
    cin >> n;

    vector <Book> books;
    while (n--) {
        string id, name, author;
        cin >> id;
        getchar();
        getline(cin, name);
        getline(cin, author);

        string line;
        getline(cin, line);

        stringstream ssin(line);
        string keyword;
        set <string> keywords;
        while (ssin >> keyword) keywords.insert(keyword);

        string publisher, year;
        getline(cin, publisher);
        cin >> year;

        books.push_back({id, name, author, keywords, publisher, year});
    }

    cin >> m;
    getchar();
    string line;
    while (m--) {
        getline(cin, line);
        cout << line << endl;
        string info = line.substr(3);
        char t = line[0];
        vector <string> res;
        if (t == '1') {
            for (auto &book: books)
                if (book.name == info)
                    res.push_back(book.id);
        } else if (t == '2') {
            for (auto &book: books)
                if (book.author == info)
                    res.push_back(book.id);
        } else if (t == '3') {
            for (auto &book: books)
                if (book.keywords.count(info))
                    res.push_back(book.id);
        } else if (t == '4') {
            for (auto &book: books)
                if (book.publisher == info)
                    res.push_back(book.id);
        } else {
            for (auto &book: books)
                if (book.year == info)
                    res.push_back(book.id);
        }

        if (res.empty()) puts("Not Found");
        else {
            sort(res.begin(), res.end());
            for (auto id: res) cout << id << endl;
        }
    }

    return 0;
}