1.1 --- a/two_sum/two_sum.pl	Fri May 01 12:12:07 2015 -0500
     1.2 +++ b/two_sum/two_sum.pl	Fri May 01 12:17:52 2015 -0500
     1.3 @@ -16,6 +16,11 @@
     1.4  # the two numbers (along with their indices).  Otherwise we add num to the hash
     1.5  # and loop back to read the next input number.
     1.6  
     1.7 +# Overall performance is O(N) in the worst case, since in that case we must
     1.8 +# process each input item exactly once.  (For each item, we perform one lookup
     1.9 +# into the hash, which adds only a small constant to the running time per
    1.10 +# iteration of the loop.)
    1.11 +
    1.12  # Usage: Pass the target value as a command line option, and the number array as
    1.13  # values on stdin, one item per line.
    1.14