Monkeymore Sudoku

Unique Rectangle Type

Level 6 · Orange Belt (Green Stripe)

Prerequisite: Unique RectanglesLearn next → Unique Rectangle Type 1

Overview

Unique Rectangle Type 2 is similar to Type 1, but two cells (on the same side) share an additional candidate. That extra candidate must be placed in one of them, so it can be eliminated elsewhere.

How It Works

  1. Find a potential deadly pattern rectangle with candidates {X,Y}.
  2. Two cells on the same side have one additional candidate Z (same in both).
  3. Z must be placed in one of these cells to avoid the deadly pattern.
  4. Eliminate Z from cells that see both of these "roof" cells.

Example

Find four cells forming a rectangle across 2 boxes. Two cells have only { 1, 5 }.

1 / 5

Tips & Patterns

  • The two cells with extra candidates must be in the same row or column (not diagonal).
  • The extra candidate Z is the same in both cells.
  • Type 2 makes eliminations outside the rectangle.