N = gets.to_i
c = gets.split.map(&:to_i).sort

dp = Array.new(N+1) { |l| x = []; x[l] = [0, 0]; x }
(1 .. N).each do |s|
    (0 .. N-s).each do |l|
        r = l + s
        b1, a1 = dp[l][r-1]
        b2, a2 = dp[l+1][r]
        a1 += c[r-1]
        a2 += c[l]
        dp[l][r] = [
            [a1, b1],
            [a2, b2],
            ].max_by { |(a, b)| a.abs - b.abs }
    end
end
a, b = dp[0][N]
puts a.abs - b.abs