Curious Cheetah
Spokes
Background
The origin of this puzzle is unknown to me.
Puzzle and Goal
An unsolved puzzle consists of a rectangular array of circles. Each circle contains a number, and there are nubs along the sides.
The goal is to fill in lines between the circle clues.
Rules
The solved grid must satisfy the following conditions:
Each clue indicates the number of lines connecting the circle to its neighbors.
No two lines can cross.