【PAT (Advanced Level) Practice】1026 Table Tennis (30 分)

A table tennis club has $N$ tables available to the public. The tables are numbered from $1$ to $N$. For any pair of players, if there are some tables open when they arrive, they will be assigned to the available table with the smallest number. If all the tables are occupied, they will have to wait in a queue. It is assumed that every pair of players can play for at most $2$ hours.

Your job is to count for everyone in queue their waiting time, and for each table the number of players it has served for the day.

One thing that makes this procedure a bit complicated is that the club reserves some tables for their $VIP$ members. When a VIP table is open, the first $VIP$ pair in the queue will have the privilege to take it. However, if there is no $VIP$ in the queue, the next pair of players can take it. On the other hand, if when it is the turn of a VIP pair, yet no $VIP$ table is available, they can be assigned as any ordinary players.

Input Specification:
Each input file contains one test case. For each case, the first line contains an integer ​​​N​​​ $(≤10000)$ - the total number of pairs of players. Then $N$ lines follow, each contains $2$ times and a $VIP$ tag: ​​​HH:MM:SS​​​ - the arriving time, ​​P​​​ - the playing time in minutes of a pair of players, and tag - which is $1$ if they hold a $VIP$ card, or $0$ if not. It is guaranteed that the arriving time is between ​​​08:00:00​​​ and ​​21:00:00​​​ while the club is open. It is assumed that no two customers arrives at the same time. Following the players’ info, there are $2$ positive integers: ​​​K​​​ $(≤100)$ - the number of tables, and $M (< K)$ - the number of VIP tables. The last line contains $M$ table numbers.

Output Specification:
For each test case, first print the arriving time, serving time and the waiting time for each pair of players in the format shown by the sample. Then print in a line the number of players served by each table. Notice that the output must be listed in chronological order of the serving time. The waiting time must be rounded up to an integer minute(s). If one cannot get a table before the closing time, their information must NOT be printed.

Sample Input:

10
20:52:00 10 0
08:00:00 20 0
08:02:00 30 0
20:51:00 10 0
08:10:00 30 0
08:12:00 10 1
20:40:00 13 0
08:01:30 15 1
20:53:00 10 1
20:54:00 10 0
3 1
2

Sample Output:

08:00:00 08:00:00 0
08:01:30 08:01:30 0
08:02:00 08:02:00 0
08:12:00 08:16:30 5
08:10:00 08:20:00 10
20:40:00 20:40:00 0
20:51:00 20:51:00 0
20:52:00 20:52:00 0
20:53:00 20:53:00 0
4 3 2

---

#include<iostream>
#include<queue>
#include<algorithm>
#include<vector>
#include<cmath>

using namespace std;

const int N = 10010, M = 110, INF = 1000000;

int n, k, m;

struct Person{ // 球员

    int arrive_time, play_time;
    int start_time, waiting_time;
    
    bool operator < (const Person & t) const{  // sort 排序
        if(start_time != t.start_time) return start_time < t.start_time;
        return arrive_time < t.arrive_time;
    }
    bool operator > (const Person & t) const{  // 优先队列中比较大小
        return arrive_time > t.arrive_time;
    }
};

struct Table{  // 球桌

    int id;
    int end_time;
    
    bool operator > (const Table & t) const{
        if(end_time != t.end_time) return end_time > t.end_time;
        return id > t.id;
    }
};

bool is_vip_table[M];
int table_cnt[M];

vector<Person> persons;

void assign(priority_queue<Person, vector<Person>, greater<Person>> &ps, 
            priority_queue<Table, vector<Table>, greater<Table>> &ts)
{
    
    auto p = ps.top(); ps.pop();
    auto t = ts.top(); ts.pop();
    
    p.waiting_time = round((t.end_time - p.arrive_time) / 60.0);
    p.start_time = t.end_time;
    table_cnt[t.id]++;
    persons.push_back(p);
    ts.push({t.id, t.end_time + p.play_time});
}

string get_time(int secs){
    char str[20];
    sprintf(str, "%02d:%02d:%02d", secs / 3600, secs % 3600 / 60, secs % 60);
    return str;
}

int main(){
    
    cin >> n;
    
    priority_queue<Person, vector<Person>, greater<Person>> normal_persons, vip_persons;
    
    normal_persons.push({INF});
    vip_persons.push({INF});
    
    for(int i = 0; i < n; i++){
        
        int hour, minute, second;
        int play_time, is_vip;
        scanf("%d:%d:%d %d %d", &hour, &minute, &second, &play_time, &is_vip);
        
        int secs = hour * 3600 + minute * 60 + second;
        play_time = min(play_time, 120);
        play_time *= 60;
        
        if(is_vip) vip_persons.push({secs, play_time});
        else normal_persons.push({secs, play_time});
    }
    
    priority_queue<Table, vector<Table>, greater<Table>> normal_tables, vip_tables;
    
    normal_tables.push({-1, INF});
    vip_tables.push({-1, INF});
    
    cin >> k >> m;
    for(int i = 0; i < m; i++){
        
        int id;
        cin >> id;
        is_vip_table[id] = true;
    }
    
    for(int i = 1; i <= k; i++)
        if(is_vip_table[i]) vip_tables.push({i, 8 * 3600});
        else normal_tables.push({i, 8 * 3600});
    
    while(normal_persons.size() > 1 || vip_persons.size() > 1){
        
        auto np = normal_persons.top();
        auto vp = vip_persons.top();
        int arrive_time = min(np.arrive_time, vp.arrive_time);
        
        while(normal_tables.top().end_time < arrive_time){  // O(klok)
            
            auto t = normal_tables.top();
            normal_tables.pop();
            t.end_time = arrive_time;
            normal_tables.push(t);
        }
        
        while(vip_tables.top().end_time < arrive_time){
            
            auto t = vip_tables.top();
            vip_tables.pop();
            t.end_time = arrive_time;
            vip_tables.push(t);
        }
        
        auto nt = normal_tables.top();
        auto vt = vip_tables.top();
        
        int end_time = min(nt.end_time, vt.end_time);
        
        if(end_time >= 21 * 3600) break;
        
        if(vp.arrive_time <= end_time && vt.end_time == end_time) assign(vip_persons, vip_tables);
        else if(np.arrive_time < vp.arrive_time){
            
            if(nt > vt) assign(normal_persons, vip_tables);
            else assign(normal_persons, normal_tables);
        }else{
            
            if(nt > vt) assign(vip_persons, vip_tables);
            else assign(vip_persons, normal_tables);
        }
    }
    
    sort(persons.begin(), persons.end());
    
    for(auto &person: persons){
        
        cout << get_time(person.arrive_time) << ' ' << get_time(person.start_time) << ' ';
        cout << person.waiting_time << endl;
    }
    
    cout << table_cnt[1];
    for(int i = 2; i <= k; i++) cout << ' ' << table_cnt[i];
    cout << endl;
    
    return 0;
}