<![CDATA[Shikaku]]>Shikaku puzzles are puzzles which can be found in some magazines. They were invented by Nikoli, a Japanese puzzle firm. Allthough they can be drawn in black and white, the colored versions seem to be more popular. There are several websites offering them – see below They are also known as Shikaku ni Kire, rectangles, Divide by Squares and Divide by Box.

The basic is a square or rectangle which has been subdivided into rectangles. The border lines are not shown in the exercise – this is what the solver has to find out. The sizes of the rectangles are given as clues.

Example:
shikaku 5x5 exercise

The solution:
shikaku 5x5 nr 1 solution

As you can see in the examples above:
(1) Only rectangles are used;
(2) Every rectangle has exactly 1 square indicating its size;

Here are some puzzles with them:
1) Problem 6×6

shikaku 6x6 nr 1 exercise

2) problem 7×7

shikaku 7x7 nr 1 exercise

3) problem 12×12

shikaku 2015-03-05 12x12 exercise

There are several apps for your android smartphone or ipad around. Sites which offer shikaku puzzles are:

  1. http://www.nikoli.com/en/puzzles/shikaku/
  2. http://www.mathinenglish.com/Shikaku.php

You can check your solutions here, here and here

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