【PAT乙级】1095 解码PAT准考证 (25 分)

题目地址

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<string>
#include<vector>
#include<map> 
#include<unordered_map> 
using namespace std;
int n,m;
const int N=1e5+10;
struct student
{
	string s;
	int test;
	int day;
	int score;
}a[N];
bool cmp(student a,student b)
{
	if(a.score==b.score)
		return a.s<b.s;
	return a.score>b.score;
}
bool cmp1(student a,student b)
{
    if(a.score==b.score)
		return a.test<b.test;
	return a.score>b.score;
}
int main(void)
{
	scanf("%d%d",&n,&m);
	for(int i=0;i<n;i++)
	{
		cin>>a[i].s;
		scanf("%d",&a[i].score);
		a[i].test=stoi(a[i].s.substr(1,3));
		a[i].day=stoi(a[i].s.substr(4,6));
	}
	sort(a,a+n,cmp);
	for(int i=1;i<=m;i++)
	{
		int op; scanf("%d",&op);
		if(op==1)
		{
			char c; scanf(" %c",&c);
			printf("Case %d: %d %c\n",i,op,c);
			bool flag=true;
			for(int i=0;i<n;i++)
			{
				if(a[i].s[0]==c) 
				{
					printf("%s %d\n",a[i].s.c_str(),a[i].score);
					flag=false;
				}
			}
			if(flag) puts("NA");
		}
		else if(op==2)
		{
			int c; scanf("%d",&c);
			int cnt=0,sum=0;
			printf("Case %d: %d %d\n",i,op,c);
			for(int i=0;i<n;i++)
			{
				if(a[i].test==c) cnt++,sum+=a[i].score;
			}
			if(cnt) printf("%d %d\n",cnt,sum);
			else puts("NA");
		}
		else
		{
			int c; scanf("%d",&c);
			printf("Case %d: %d %06d\n",i,op,c);
			vector<student>ans;
			unordered_map<int,int>s;
			for(int i=0;i<n;i++)
			{
				if(a[i].day==c)
				{
					s[a[i].test]++;
				}
			}
			for(auto t=s.begin();t!=s.end();t++)
			{
				struct student temp;
				temp.test=t->first;
				temp.score=t->second;
				ans.push_back(temp);
			}
			sort(ans.begin(),ans.end(),cmp1);
			if(ans.size())
			{
				for(int i=0;i<ans.size();i++)
				{
					printf("%d %d\n",ans[i].test,ans[i].score);
				}
			}
			else puts("NA");
		}
	}
	return 0;
}