#!/bin/ruby

def largestValue(a)
    for i in 0...a.length
        for j in i+1...a.length
        end
    end
    # Return the largest value of any of A's nonempty subarrays.
end

n = gets.strip.to_i
a = gets.strip
a = a.split(' ').map(&:to_i)
result = largestValue(A)
puts result