A1153 Decode Registration Card of PAT

#include<iostream>
#include<vector>
#include<map>
#include<string>
#include<cstring>
#include<cstdio>
#include<algorithm>
#include<set>
#include<queue>
#include<unordered_map>
#include<cmath>
using namespace std;
const int maxn = 10010;
struct node
{
	string id;
	int score;
};

bool cmp(node a, node b)
{
	return a.score != b.score ? a.score > b.score : a.id < b.id;
}


int main()
{
	int n, m,q;
	cin >> n >> m;
	vector<node>v(n);
	string s; 
	for (int i = 0; i < n; i++)
	{
		cin >> v[i].id >> v[i].score;		
	}
	for (int i = 1; i <= m; i++)
	{
		cin >> q >> s;
		int people = 0, allscore = 0;
		printf("Case %d: %d %s
", i, q, s.c_str());
		vector<node>ans;
		if (q == 1)
		{
			for (int j = 0; j < v.size(); j++)
			{
				if (v[j].id[0] == s[0]) 
					ans.push_back(v[j]);
			}
		}
		else if (q == 2)
		{
			for (int j = 0; j < v.size(); j++)
			{
				if (v[j].id.substr(1, 3) == s)
				{
					people++;
					allscore += v[j].score;
				}
			}
			if (people != 0) printf("%d %d
", people, allscore);
		}
		else if (q == 3)
		{
			unordered_map<string, int> m;
			for (int j = 0; j < n; j++)
				if (v[j].id.substr(4, 6) == s) m[v[j].id.substr(1, 3)]++;
			for (auto it = m.begin(); it != m.end(); it++)
				ans.push_back({ it->first,it->second });
		}
		sort(ans.begin(), ans.end(), cmp);
		for (int j = 0; j < ans.size(); j++)
			printf("%s %d
", ans[j].id.c_str(), ans[j].score);
		if (((q == 1 || q == 3) && ans.size() == 0) || (q == 2 && people == 0)) printf("NA
");
	}

}