Pipeline is similar to other "snake drawing" puzzles.
Puzzle and Goal
An unsolved puzzle consists of a rectangular grid. There are some number clues along the edges, and some portions of pathway already filled in.
The goal is to complete the pathway through the grid.
The goal is to complete a loop.
The solved grid must satisfy the following conditions:
The path can go though any cell at most one time.
Numbers on the edges indicate how many cells in that rank contain a portion of the path.
All clues must be used; the path starts and ends at the indicated circles.