Shikaku

Rules

Divide the grid into rectangles along the grid lines such that each cell is in exactly one rectangle and each rectangle contains exactly one given number. The number must equal the area of the rectangle (in cells).

(Rules from PGP IB, example from WPC 2019 IB)

History of the puzzle

First appeared on Nikoli volume 27 (1989). Invented by Yoshinao Anpuku. The original title 四角に切れ means "divide into rectangles."

Variants

Double Shikaku

First appeared on WPC 2018/Round 10, "Double Trouble". The puzzle was written by Jiří Hrdina (Czech Rep.).

In the given grid, one of the paired (adjacent) clues belong to one Shikaku puzzle and the other half belong to the other. Reconstruct two puzzles and solve them.

(Example from WPC 2018 IB)

Appearances in the past WPCs

• WPC 2019/World Cup Round 1 (Knapp Daneben) by Roland Voigt
• WPC 2019/Round 9 by Ulrich Voigt
• WPC 2019/World Cup Playoffs by Erhard Notz
• WPC 2018/Round 5 by Jiří Hrdina
• WPC 2018/Round 10 (Double Shikaku) by Jiří Hrdina
• WPC 2018/Round 13 (Knapp Daneben) by Jiří Hrdina
• WPC 2017/Round 1 (Coded) by Rajesh Kumar
• WPC 2017/Round 16 by Swaroop Guggilam
• WPC 2016/Round 2 by Matej Uher
• WPC 2016/Round 14 (part of a Permaculture hybrid) by Matúš Demiger
• WPC 2014/Round 3
• WPC 2014/Round 6
• WPC 2014/Round 14
• WPC 2013/Part 6 (Shikaku, Doubled Shikaku)
• WPC 2011/Part 9