#!/usr/bin/perl -w

use strict;

my $length = 4;  # max length of the word to find
my $find = "test"; # the word to find

sub gen_word {
  my $prev = shift;
  my $len = shift;

  if ($len == 1) {
    for (my $idx = 65; $idx <= 122; $idx++) {
      my $word = $prev . chr($idx);
      print "word: $word\n";
      if ($find eq $word) {
        print "found: " . $word . "\n";
        exit();
      }
    }
  } else {
    for (my $idx = 65; $idx <= 122; $idx++) { &gen_word($prev . chr($i
+dx), $len - 1); }
  }
}

&gen_word("", $length);

1;
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I still think your question (and maybe your quest) is a bit too vague for us to help much. Be crisp. Decide on one thing you want to get done, and be as clear and specific as possible about your objective, and we can help with the strategy and tactics.

For example, cycling through all possible "words" is one algorithm. You have to be specific about what constitutes a "word." In MasterMind, you choose a known number of colored pegs in sequence. Passwords have far more letters and symbols which can appear in each position, and you don't even know the length. In a trivia game, your answer "word" might be something like "the Battle of Bull Run" which is a pretty long word to guess if you're trying every possible permutation including common punctuation.

Once you decide what a "word" is, you can write a program to cycle through all possible permutations pretty easily, even if it takes the computer several years to run that program.

Your other part of the problem is to decide if a given guess "word" is the correct answer, or even is a word worth trying. MasterMind only gives you a handful of tries before you lose, so you have to pay attention to the feedback. A login prompt might lock the account after three tries without giving any feedback at all. And trivia game show hosts rarely let you try more than one answer and only give you a few seconds to think about it.

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