Hebi-Ichigo is a logic puzzle invented by Nikoli. The goal is to insert the numbers 1 to 5 according to the rules:
- Numbers form a sequential chain of five cells from 1 ("head") to 5 ("tail") connected horizontally and vertically ("snake").
- Snakes cannot touch other snakes horizontally or vertically, diagonally is allowed.
- Snakes are not allowed to appear in front of the head of another snake. The snake’s eyes are located on a side of the head (cell with number 1), opposite from the side its body (cell with number 2) is connected to. A snake looks in the direction of its eyes until a black cell or the edge of the grid is reached.
- The number in the black cell shows the value of the nearest number in the direction of the arrow. This number must appear before any other black cells. A black cell with a zero means there is no snake in the direction of the arrow until the next black cell or the edge of the grid.
Cross+A can solve puzzles from 3 x 3 to 30 x 30.