1055 The World‘s Richest (25分) C++ y神巧妙解法

Forbes magazine publishes every year its list of billionaires based on the annual ranking of the world’s wealthiest people. Now you are supposed to simulate this job, but concentrate only on the people in a certain range of ages. That is, given the net worths of N people, you must find the M richest people in a given range of their ages.

Input Specification:

Each input file contains one test case. For each case, the first line contains 2 positive integers: N (≤10​5​​) - the total number of people, and K (≤10​3​​) - the number of queries. Then N lines follow, each contains the name (string of no more than 8 characters without space), age (integer in (0, 200]), and the net worth (integer in [−10​6​​,10​6​​]) of a person. Finally there are K lines of queries, each contains three positive integers: M (≤100) - the maximum number of outputs, and [Amin, Amax] which are the range of ages. All the numbers in a line are separated by a space.

Output Specification:

For each query, first print in a line Case #X: where X is the query number starting from 1. Then output the M richest people with their ages in the range [Amin, Amax]. Each person’s information occupies a line, in the format

Name Age Net_Worth

The outputs must be in non-increasing order of the net worths. In case there are equal worths, it must be in non-decreasing order of the ages. If both worths and ages are the same, then the output must be in non-decreasing alphabetical order of the names. It is guaranteed that there is no two persons share all the same of the three pieces of information. In case no one is found, output None.

Sample Input:

12 4
Zoe_Bill 35 2333
Bob_Volk 24 5888
Anny_Cin 95 999999
Williams 30 -22
Cindy 76 76000
Alice 18 88888
Joe_Mike 32 3222
Michael 5 300000
Rosemary 40 5888
Dobby 24 5888
Billy 24 5888
Nobody 5 0
4 15 45
4 30 35
4 5 95
1 45 50

Sample Output:

Case #1:
Alice 18 88888
Billy 24 5888
Bob_Volk 24 5888
Dobby 24 5888
Case #2:
Joe_Mike 32 3222
Zoe_Bill 35 2333
Williams 30 -22
Case #3:
Anny_Cin 95 999999
Michael 5 300000
Alice 18 88888
Cindy 76 76000
Case #4:
None

y神引入了一个idx[N]的数组，初始值都赋值为0，然后套在一个while(n–)查找，在每一次查找过程中进行一次for循环找到应该输出的那一个下标，之后直接输出，这里设置一个初始值为-1的t,如果查找完后还是-1，则说明完全没有找到，直接break输出None，否则循环继续。

#include<bits/stdc++.h>
using namespace std;

const int N =1e5+10;
int idx[N];

struct peo{
	string name;
	int age;
	int wealth;
	
	bool operator < (const peo& x)
	{
		if(wealth!=x.wealth) return wealth>x.wealth;
		if(age!=x.age) return age < x.age;
		return name < x.name;
	}
	
};

vector<peo> mp[N];
int main()
{	
	int n,m,ag,wea; scanf("%d%d",&n,&m);
	char name[10];
	for(int i=0;i<n;i++)
	{
		scanf("%s%d%d",name,&ag,&wea);
		mp[ag].push_back({name,ag,wea});
	}
	for(auto &p:mp) sort(p.begin(),p.end());
	for(int i=1;i<=m;i++)
	{
		printf("Case #%d:\n",i);
		int co,amin,amax;
		scanf("%d%d%d",&co,&amin,&amax);
		memset(idx, 0, sizeof idx);
		bool flag=false;
		while(co--)
		{
			int t=-1;
			for(int j=amin;j<=amax;j++)
			{
				if(idx[j]<mp[j].size())
				{
					if(t==-1 || mp[j][idx[j]] < mp[t][idx[t]])
					{
						t = j;
					}
				}
			}
			if(t==-1) break;
			auto& temp = mp[t][idx[t]];
			idx[t]++;
			printf("%s %d %d\n",temp.name.c_str(),temp.age,temp.wealth);
			flag = true;
		}
		if(flag==false)
			printf("None\n");
	}
	return 0;
}