1022 Digital Library (30 分)

思想

结构体去做 自定义排序方式实现从小到大编号
存储string的vector的使用
有点小坑是编号的7位输出 PTA老把戏
substr的使用截取查询段
cin.peek()窥视实现多个keyword的获取
输入方面cin.get()有点小讲究
如果要用cin 无需使用 因为cin是智能指针可以跳过缓冲区的无效字符(如空格、回车)
如果要用getline 则需要加一个cin.get()在下一次读取前清空残余缓存
getline与getline之间无需使用cin.get()
剩下的慢慢模拟吧
到这里讲解结束

AC代码

#include <iostream>
#include <cstdio>
#include <vector>
#include <string>
#include <algorithm>
using namespace std;
struct book{
    int id;
    string title;
    string author;
    vector<string> keywords;
    string publisher;
    string year;
}books[10010];
bool cmp(book a, book b){
    return a.id < b.id;
}
int n;
string qword;
void q1(){
    string qtitle = qword.substr(3);
    int flag = 0;
    cout << qword << endl;
    for (int i = 0; i < n; i++){
        if (qtitle == books[i].title){
            flag = 1;
            printf("%07d\n", books[i].id);
        }
    }
    if (!flag) cout << "Not Found" << endl;
}
void q2(){
    string qauthor = qword.substr(3);
    int flag = 0;
    cout << qword << endl;
    for (int i = 0; i < n; i++){
        if (qauthor == books[i].author){
            flag = 1;
            printf("%07d\n", books[i].id);
        }
    }
    if (!flag) cout << "Not Found" << endl;
}
void q3(){
    string qkeyword = qword.substr(3);
    int flag = 0;
    cout << qword << endl;
    for (int i = 0; i < n; i++){
        for (int j = 0; j < books[i].keywords.size(); j++){
            if (qkeyword == books[i].keywords[j]){
                flag = 1;
                printf("%07d\n", books[i].id);
                break;
            }
        }
    }
    if (!flag) cout << "Not Found" << endl;
}
void q4(){
    string qpublisher = qword.substr(3);
    int flag = 0;
    cout << qword << endl;
    for (int i = 0; i < n; i++){
        if (qpublisher == books[i].publisher){
            flag = 1;
            printf("%07d\n", books[i].id);
        }
    }
    if (!flag) cout << "Not Found" << endl;
}
void q5(){
    string qyear = qword.substr(3);
    int flag = 0;
    cout << qword << endl;
    for (int i = 0; i < n; i++){
        if (qyear == books[i].year){
            flag = 1;
            printf("%07d\n", books[i].id);
        }
    }
    if (!flag) cout << "Not Found" << endl;
}
int main(){
    cin >> n;
    for (int i = 0; i < n; i++){
        cin >> books[i].id;
        cin.get();
        getline(cin, books[i].title);
        getline(cin, books[i].author);
        while (cin.peek() != '\n'){
            string key;
            cin >> key;
            books[i].keywords.push_back(key);
        }
        cin.get();
        getline(cin, books[i].publisher);
        cin >> books[i].year;
    }
    sort(books, books+n, cmp);
    int query;
    cin >> query;
    cin.get();
    while (query--){
        getline(cin, qword);
        switch (qword[0]){
            case '1': q1(); break;
            case '2': q2(); break;
            case '3': q3(); break;
            case '4': q4(); break;
            case '5': q5(); break;
        };
    }
    return 0;
}