From: Paul McMahon <pm@...>
Date: 2008-06-20T11:11:40+09:00
Subject: Re: little problem (google hiring puzzle)

Kevin Compton wrote:
> how bad is this?
> 
> inp = [4, 3, 2, 1, 2]
> outp = []
> inp.each_with_index {|val, idx| inp[idx] = 1; outp << inp.inject(1) { |prod,
> val2| prod * val2 }; inp[idx] = val}
> 
> 

O(n^2).  You are iterating through inp within inp (inject will iterate
through each element).