G. Interference Signal

Dr.Kong’s laboratory monitor some interference signals. The interference signals can be digitized into a series of positive integer. May be, there are N integers a1,a2,…,an.

 

Dr.Kong wants to know the average strength of a contiguous interference signal block. the block must contain at least M integers.

 

Please help Dr.Kong to calculate the max i  mum average strength, given the constraint.

Input

The input contains K test cases. Each test case specifies:
* Line 1: Two space-separated integers, N and M.
* Lines2~line N+1: ai (i=1,2,…,N)
1 ≤ K≤ 8, 5 ≤ N≤ 2000, 1 ≤ M ≤ N, 0 ≤ ai ≤9999

Output

For each test case generate a single line containing a single integer that is 1000 times the maximal average value. Do not perform rounding.

Sample Input

2 
10 6
6 
4
2
10
3
8
5
9
4
1
5 2
10
3
8
5 
9

Sample Output

6500
7333
#include<cstdio>
#include<algorithm>
#include<cstring>
using namespace std;
const int maxn=2009;
long long a[maxn];
int main()
{
    int t;
    int k;
    int n;
    scanf("%d",&t);
    while(t--)
    {
        memset(a,0,sizeof(a));
        scanf("%d%d",&n,&k);
        for(int i=1;i<=n;i++)
        {
            scanf("%lld",&a[i]);
            a[i]+=a[i-1];
        }
        double ave=0;double maxx=0;
        for(int i=0;i<=n;i++)
        {
            for(int j=n;j>=1;j--)
            {
                if(j-i<k) break;
                ave=(double)(a[j]-a[i])/(j-i);
                maxx=max(ave,maxx);
            }
        }

        long long ans=(long long)(maxx*1000);
        printf("%lld\n",ans);
    }
    return 0;
}