This is a Nikoli original.
Puzzle and Goal
An unsolved puzzle consists of a rectangular grid. Some cells contain a clue, consisting of a number and an arrow.
The goal is to blacken some of the cells.
The solved grid must satisfy the following conditions:
The numbers in white cells indicate how many black cells the arrow points to (clues in blackened cells are irrelevant).
Black cells may not be orthogonally adjacent.
White cells must form a single orthogonally contiguous region.