Mystery Master

All Tired Out

Michael Benson


Introduction

This three-star logic puzzle has 3 noun types, 5 nouns per type, only 1 link, 8 facts, and 2 rules with triggers. It needs only 75 marks and 3 grids. Before solving this puzzle, let's take a look at its rules.

Rules

To test the rules for this puzzle, disable triggers and laws. Here are the rules for this puzzle.

  1. Marge wasn't the second of the three women in line.
  2. Grace stood next to at least one man in line.

To violate rule 1 without violating the second rule or any facts, place Lisa second, Marge third, and Grace fourth. You will see a message indicating you violated the first rule. You will need to undo your marks.

To violate rule 2, place Grace first and Marge second. You will see a message indicating you violated the second rule. You will need to undo your marks.

Question: What should happen if Grace is 1st, but no man is 2nd?

Triggers

Besides checking that a mark does not contradict a clue, a rule can also check that if a certain condition exists, then a mark should be entered. A mark that is entered by a rule is called a trigger. Both of the rules for the example puzzle also contain triggers. Please enable triggers.

The first rule checks that if Grace is before the third person in line and Lisa is after the third person in line, then Grace cannot be the third person in line. Though this rule was written for this exact condition, you can write your rules as general as you want. To invoke this trigger, put Grace second and Lisa fourth.

The second rule triggers a mark based on certain conditions as well. If no man can be second in line, then Grace is not first. If no man can be fourth in line, then Grace is not last. And if no man can be second second and fourth, then Grace is not third. Adding triggers to a rule enabled this puzzle to be solved without making any assumptions. Make sure rules, triggers, and laws are all enabled before solving this puzzle.

Links

There are 4 links for this puzzle "with", "just ahead", "three places ahead", and "next to". All of the links have the noun type "Order", and the first 3 are one-to-one.

Facts

This puzzle has 8 facts, where facts 1, 2, 3, 5, and 6 are type 1 (i.e., the link is With). Fact 7 is type 3 (same noun type for each noun), while facts 4 and 8 are type 4 (both nouns have different types).

Examining Two Facts

To solve this puzzle, the following two facts need to be examined together. Note that both links are one-to-one.

  1. The person who bought whitewall tires stood three places ahead of the one who requested a wheel alignment (clue 4).
  2. Jeff was just ahead of the person who had shock absorbers installed (clue 6).

Here are the possible positions for the nouns in both facts.

If Jeff bought the tires, he had to be 1st, which means the shocks are 2nd and the alignment is 4th.

Conclusion

This is a challenging three-star puzzle because of the rules and triggers.