Given an array \(a\) of length \(n\). You need to find a subarray \(a[l..r]\) with length at least \(k\) with the \(largest\) median.
A median in an array of length \(x\) is the \(⌊(x+1)/2⌋-th\) smallest element of it. For example: median([1,2,3,4])=2, median([3,2,1])=2, median([2,1,2,1])=1.
Subarray \(a[l..r]\) is a sub-array \(a\), it includes \(a_l, a_{l+1} ... a_r\) for \(1≤l≤r≤n\), its length is \(r−l+1\).