Makaro

Makaro is a logic puzzle published by Nikoli. A rectangular or square grid is divided into regions. Each region must be filled with each of the digits from 1 to the number of cells in the region. The grid may contain the black cells with arrows. The arrow points at the biggest number among the four cells around (up, under, left, right) the black cell. When two numbers are orthogonally adjacent across a region boundary, the numbers must be different.

Makaro

Cross+A can solve puzzles from 3 x 3 to 30 x 30.