The origin of this puzzle is not known.
Puzzle and Goal
An unsolved puzzle is a rectangular grid. Clues are a start, an end, and number clues.
The goal is to draw a single line that satisfies the clues.
The solved grid must satisfy the following conditions:
The line starts at the beginning, ends at the end, and goes through each cell exactly once, travelling orthogonally.
The line may only turn after going through a number X, and then must turn X times before going through another number.