#include<cstdio>
#include<algorithm>
using namespace std;
int mas,ans,n,k,a[100001],l[100001];
int rmq(int ll,int r,int p[])
{
    sort(p+ll,p+r+1);
    return p[(ll+r)/2];
}
int main()
{
    freopen("player.in","r",stdin);
    freopen("player.out","w",stdout);
    scanf("%d%d",&n,&k);
    for(int i=1;i<=n;i++)
    {
        scanf("%d",l+i);
        a[i]=a[i-1]+l[i];
    }
    
    for(int i=k;i<=n;i++)
    {
        for(int j=i-k;j>=0;j--)
        {
            if(mas<(a[i]-a[j]))
            {
                mas=a[i]-a[j];
                ans=max(ans,rmq(j+1,i,l));
                break;
            } 
        }
    }
    printf("%d",ans);
    return 0;
}