maxval.rb

def maximum(arr)
  while arr.length>1  
    arr.each do |i|
      if i+1>i
        arr.delete(i)
      end
    end
  end
  if arr.length==0
    return nil
  else
    return arr[0].to_i
  end
end


result = maximum([2, 42, 22, 02])
puts "max of 2, 42, 22, 02 is: #{result}"
 
 
result = maximum([])
puts "max on empty set is: #{result.inspect}"

result = maximum([-23, 0, -3])
puts "max of -23, 0, -3 is: #{result}"

result = maximum([6])
puts "max of just 6 is: #{result}"