思路：边读入数据边处理，安题干要求分类保存。查询时直接输出。

第三类按日期查询时数据不好保存，还是按y总的方法查询时处理更简单。

C++ 代码

#include <iostream>
#include <string>
#include <unordered_map>
#include <vector>
#include <algorithm>

using namespace std;

const int S = 1010;

struct Node
{
    string id;
    int score;
};

struct Site
{
    int cnt, sum;
    Site() {
        cnt = 0;
        sum = 0;
    }
}site[S];

bool cmp(Node a, Node b) {
    if (a.score != b.score) return a.score > b.score;
    else return a.id < b.id;
}

vector<Node> la, lb, lt;
unordered_map<string, unordered_map<string, int>> dateHash;
int main() {
    int n, q;
    cin >> n >> q;
    for (int i = 0; i < n; i++)
    {
        Node t;
        cin >> t.id >> t.score;

        if (t.id[0] == 'A') la.push_back(t);
        if (t.id[0] == 'B') lb.push_back(t);
        if (t.id[0] == 'T') lt.push_back(t);

        string s = t.id.substr(1, 3);
        site[stoi(s)].cnt++;
        site[stoi(s)].sum += t.score;

        string date = t.id.substr(4, 6);
        dateHash[date][s]++;
    }

    sort(la.begin(), la.end(), cmp);
    sort(lb.begin(), lb.end(), cmp);
    sort(lt.begin(), lt.end(), cmp);

    for (int i = 1; i <= q; i++)
    {
        string t, c;
        cin >> t >> c;

        printf("Case %d: %s %s\n", i, t.c_str(), c.c_str());

        if (t == "1")
        {
            if (c[0] == 'A') {
                if (la.empty()) puts("NA");
                else
                    for (auto it : la) printf("%s %d\n", it.id.c_str(), it.score);
            }
            if (c[0] == 'B') {
                if (lb.empty()) puts("NA");
                else
                    for (auto it : lb) printf("%s %d\n", it.id.c_str(), it.score);
            }
            if (c[0] == 'T') {
                if (lt.empty()) puts("NA");
                else
                    for (auto it : lt) printf("%s %d\n", it.id.c_str(), it.score);
            }
        }
        else if (t == "2")
        {
            int idx = stoi(c);
            if (site[idx].cnt == 0) puts("NA");
            else printf("%d %d\n", site[idx].cnt, site[idx].sum);
        }
        else
        {
            vector<pair<int, string>> rooms;
            for (auto item : dateHash[c]) rooms.push_back({ -item.second, item.first });

            sort(rooms.begin(), rooms.end());
            if (rooms.empty()) puts("NA");
            else
                for (auto room : rooms)
                    printf("%s %d\n", room.second.c_str(), -room.first);
        }
    }
    return 0;
}