sicily--1046. Plane Spotting

/* A period P1 is better than another period P2 if:
**the number of planes per quarter in P1 is higher than in P2;
**the numbers are equal but P1 is a longer period (more quarters);
** the numbers are equal and they are equally long, but period P1 ends earlier.
*/

#include<iostream>
#include<queue>//使用优先级队列
#include<vector>
using namespace std;

struct Node//某段时间
{
int start;
int end;
double avr;//该段时间内平均每个quarter的飞机
};

struct cmp
{
bool operator()(const Node &n1, const Node &n2)
{
/* A period P1 is better than another period P2 if:
**the number of planes per quarter in P1 is higher than in P2;
**the numbers are equal but P1 is a longer period (more quarters);
** the numbers are equal and they are equally long, but period P1 ends earlier.
*/
if(n1.avr != n2.avr)
return n1.avr < n2.avr;//相当于less，大顶堆;   平均飞机数更多
else if((n1.end - n1.start) != (n2.end - n2.start))
return (n1.end - n1.start) < (n2.end - n2.start); //相当于greater,小顶堆;  平均飞机数一样，长度更长
else
return n1.end > n2.end;//平均飞机数一样，长度一样，更早的结束
}
};
int main()
{
int runNum;
cin >> runNum;
for(int i = 1; i <= runNum; i++)
{
int quarters;
cin >> quarters;
int output;//输出的period数
cin >> output;
int min;//要求的最小quarter数
cin >> min;

int *arr = new int[quarters];
for(int j = 0; j < quarters; j++)
{
cin >> arr[j];//每个quarter内的飞机数
}
vector<Node> v;
//遍历计算
for(int m = quarters; m >= min; m--)//因为同等程度下，长的优先
{
for(int j = 0; j < quarters; j++)
{
/*
**譬如：quarters = 3， 数组的下标是0，1，2； min = 3
*/
if(j + m > quarters)//越界
break;
int sum = 0;
for(int k = 0; k < m; k++)
{
sum = sum + arr[j + k];
}
Node temp;
temp.start = j + 1;
temp.end = j + m;
temp.avr = (double)sum / m;//平均每个period内的飞机数
v.push_back(temp);
}
}
priority_queue<Node, vector<Node>, cmp> Q(v.begin(), v.end());
cout << "Result for run " << i << ":" << endl;
for(int j = 0; j < output; j++)
{
if(Q.empty())
break;
else
{
Node temp = Q.top();
Q.pop();
cout << temp.start << "-" << temp.end << endl;
}
}
}
return 0;
}