Jeff's friends know full well that the boy likes to get sequences and arrays for his birthday. Thus, Jeff got sequence p₁,p₂,...,p_n for his birthday.

Jeff hates inversions in sequences. An inversion in sequence a₁,a₂,...,a_n is a pair of indexes i,j (1≤i<j≤n), such that an inequality a_i>a_j holds.

Jeff can multiply some numbers of the sequence p by -1. At that, he wants the number of inversions in the sequence to be minimum. Help Jeff and find the minimum number of inversions he manages to get.

The first line contains integer n (1≤n≤2000). The next line contains n integers − sequence p₁, p₂, ..., p_n (|p_i|≤10⁵). The numbers are separated by spaces.

In a single line print the answer to the problem − the minimum number of inversions Jeff can get.