Hitori

Hitori (Japaneseひとり に し て くれHitori ni shite kure, dt leave me alone ) is a mystery of the Japanese publisher Nikoli. It first appeared in Puzzle Communication Nikoli 29 ( March 1990). The puzzle is also known under the name stroke of the pen.

Regulate

Hitori is played on a square lattice. All squares contain numbers. The goal is to identify squares with "wrong" colored numbers, and highlight or otherwise emphasize the following characteristics are fulfilled by:

  • In each row and in each column each digit occurs only once is not it highlighted.
  • The highlighted squares are not adjacent to an edge well.
  • The white- lasting squares must be related to each other via edges.

Normally, the solution through the given numbers is clearly defined.

Solution methods

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