max_slice.rb

def max_slice(a)
  max_start,max_end = 0,0
  largest_sum = 0
  curr_start,curr_end = 0,0
  curr_sum = 0
  for i in 0..a.length-1 
    if (curr_sum + a[i]  < 0 ) then
      curr_start = i+1
      curr_sum = 0
    elsif (curr_sum + a[i] > curr_sum) then  
      curr_sum = curr_sum + a[i]
      curr_end = i
      if (curr_sum > largest_sum) then
        max_start, max_end = curr_start,curr_end
        largest_sum = curr_sum
      end 
    end
  end
  a[max_start..max_end]
end

p max_slice(a)
p max_slice([-3,39,2,-1,65])
p max_slice([12,-3,39,2,-1,65])
p max_slice([-5,35,39,2,-160,65])