This is a Nikoli original.
Puzzle and Goal
An unsolved puzzle consists of a square grid with circles at the intersections; some of the intersections have numbers from 0 to 4.
The goal is to place diagonal lines in each cell to satisfy the clues.
The solved grid must satisfy the following conditions:
The number clues represent the number of diagonal lines coming into each circle.
Each cell has exactly one diagonal line in it.
Diagonal lines cannot create a closed loop anywhere in the grid.
Gokigen Naname; Slalom; Slant