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Lizely

Logic Grid Puzzle

Solve one original three-person logic grid with accessible selectors and an independent exhaustive proof that all four clues are necessary and the answer is unique.

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How to use

  1. 1.Read all four clues, then assign one pet and one visit day to each person; every pet and day must appear exactly once.
  2. 2.Use the native selectors with touch, mouse, or keyboard, clearing an existing owner before moving a pet or day to another row.
  3. 3.Check only after all six selections are filled; one distinct wrong grid is repairable, while the unique solution awards exactly 1,000 points.

About Logic Grid Puzzle

Logic Grid Puzzle is a compact deterministic deduction game built around one original Lizely fixture. Ava, Ben, and Cora each brought a different pet and visited on a different day. The pets are Cat, Dog, and Owl. The days are Monday, Tuesday, and Wednesday. Four visible clues constrain the pairings, and the task is to assign one pet and one day to every person without reusing either kind of value.

The clues are deliberately short and fully disclosed. Ava did not visit on Monday. The dog owner visited on Monday. Cora visited on Wednesday. Ava did not bring the cat. Together, these statements leave exactly one one-to-one grid: Ava brought the Owl on Tuesday, Ben brought the Dog on Monday, and Cora brought the Cat on Wednesday. The solution is not drawn from an external puzzle book, exam, feed, or branded game.

Each row uses native select controls. They work with touch, mouse, and standard keyboard navigation without requiring drag gestures or tiny grid cells. Tab moves through the controls, arrow keys change an option, and the browser's usual Enter or Space behavior opens a select where supported. Every control has a person-specific accessible name, and every option remains understandable without color.

Uniqueness is enforced while editing. Once a pet is assigned to one person, that pet is disabled in the other pet selectors and labeled with its current owner. Days behave the same way. The pure state boundary independently rejects a duplicate mapping, leaves the assignment grid unchanged, and returns an explicit conflict message. Clear the existing owner first if the value needs to move to another row.

Incomplete checking is safe. Pressing Check grid before all six selections are filled reports that the grid is unfinished but records no wrong attempt, changes no score, and does not deadlock the run. This makes an accidental click harmless and lets a player reason incrementally. Reset grid and the shared Restart control restore the exact initial empty state at any time.

A complete wrong grid is recorded by a canonical person, pet, and day signature. The first distinct wrong grid remains repairable: change any selections and check again. Submitting that identical wrong grid repeatedly is an atomic no-op, so a double click or repeated activation cannot consume the second error. The history contains only distinct complete wrong assignments.

A second distinct complete wrong grid ends the run. The interface then discloses the unique answer and freezes every assignment and check control. A correct grid is also terminal. It awards exactly 1,000 points, updates the shared local best score, and freezes the solved arrangement. There is no time bonus, partial credit, clue multiplier, or hidden score calculation.

The fixture has a finite proof rather than a claim based on visual inspection. Three pets can be assigned to three named people in 3! orders, and three days can independently be assigned in another 3! orders. Their product is 36 possible one-to-one grids. The production logic can enumerate that finite universe, but release validation does not treat production code as its own oracle.

The independent test oracle defines separate literal person, pet, and day arrays, its own permutation routine, and four separate clue predicates. It enumerates all 36 pet-order and day-order pairs and obtains exactly one solution. The test then compares that answer with the production result. This catches a production predicate or enumeration error instead of merely repeating an expected final string.

Clue minimality is proven too. The oracle removes one clue at a time while retaining the other three. Without Ava's Monday restriction, three grids remain. Without the dog-owner Monday clue, four remain. Without Cora's Wednesday clue, four remain. Without Ava's cat restriction, two remain. Because every removal produces more than one candidate, each of the four clues materially contributes to the unique answer.

Authored golden cases also cover the person, pet, and day sets; the exact answer; incomplete safety; duplicate conflict atomicity; first-error repair; repeated-error deduplication; second-distinct-error deadlock; the exact score; reset shape; and frozen terminal states. These checks are deterministic and run without a network, random seed, clock, locale lookup, or external service.

Everything runs in the current browser tab. Assignments, checks, score, and keyboard activity are not uploaded. No account, payment, API call, server-side solver, new package, or runtime dependency is used. Once the page has loaded, the fixed puzzle remains playable without fetching changing content.

The layout is designed for small screens as well as desktops. At a 390-pixel viewport, each person row stacks its name, pet selector, and day selector rather than forcing a wide spreadsheet. Controls retain touch-friendly height, feedback is announced through a polite live region, status includes text counts, and the unique answer appears in text after deadlock. The shared double-Escape Boss Mode temporarily covers the game while preserving the same local state.

Logic Grid Puzzle is recreational entertainment. Its disclosed fixture, limited attempts, and fixed 1,000-point score do not measure intelligence, education, suitability for employment, health, memory, or psychological ability. For a clean solve, begin with Cora's fixed Wednesday visit and the dog owner's fixed Monday visit, then combine Ava's two exclusions to determine the remaining pet and day.

Methodology & sources

Represent the original three-person fixture as two one-to-one mappings, reject duplicate pet or day assignments atomically, and canonicalize complete grids by person order. Treat incomplete checks as penalty free, deduplicate an identical complete wrong grid as an identical-state no-op, permit one distinct wrong grid, deadlock on the second, award exactly 1,000 for the unique solution, and freeze both terminal states. Independently enumerate all 3! pet orders times all 3! day orders with separate literal clue predicates; require exactly one solution and more than one candidate whenever any single clue is removed.

Frequently asked questions

Does this puzzle really have only one answer?
Yes. An independent oracle enumerates all 36 one-to-one pet and day grids, finds only Ava–Owl–Tuesday, Ben–Dog–Monday, and Cora–Cat–Wednesday, and proves each clue is necessary.
Why can I not select a pet or day that another person already uses?
The puzzle requires one-to-one mappings. Used options are disabled and labeled, while the logic layer atomically rejects duplicate assignments without changing the grid.
Does the 1,000-point score measure reasoning ability?
No. The original fixed fixture, disclosed answer, finite two-error rule, and fixed score are entertainment behavior, not an intelligence, education, employment, health, or psychological assessment.

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