En Sun, 04 May 2008 03:35:05 -0300, George Sakkis <[EMAIL PROTECTED]> escribió: > On May 4, 2:04 am, "Gabriel Genellina" <[EMAIL PROTECTED]> wrote: >> En Sun, 04 May 2008 02:17:07 -0300, dave <[EMAIL PROTECTED]> escribió: >> >> > I made a function that takes a word list (one word per line, text file) >> > and searches for all the words in the list that are 'shifts' of >> > eachother. 'abc' shifted 1 is 'bcd' >> >> But I'd use a different algorithm. Instead of generating all posible shifts >> for a given word, I'd substract the newly read word from each previous words >> (here, "substract two words" means substract the character code for >> corresponding positions, modulo 26). Shifted words, when substracted, have >> the same number on all positions. > > A faster algorithm is to create a 'key' for each word, defined as the > tuple of ord differences (modulo 26) of consecutive characters. E.g. > the key of 'acf' is (2,3); 'c' is 2 positions after 'a' and 'f' 3 > positions after 'c'. Shifted words (and only these) have the same key.
Much better! I like it. -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
