Railroad Tracks

From WPC unofficial wiki

Rules[edit]

Draw a loop passing through centres of cells horizontally or vertically, passing through all circles. The loop must cross itself, but only in cells with a given '+'. The loop must pass straight through 'stations', i.e. numbered cells, and must travel in order from 1 to 2 and so on till N, where N is the highest number that will be placed in the grid, and then back to 1. No numbers and crosses can be placed in the grid apart from those indicated within the yarns.

(Rules and example from WPC 2017 IB)

History of the puzzle[edit]

First appeared in WPC 2000/Part I. Invented by Craig Kasper (Canada).

Variants[edit]

Japanese Railways[edit]

Addition of Paint by Numbers-style clues. First appeared on Moscow Cup 2014. Author of the puzzle was Andrey Bogdanov (Russia).

Shade some cells. The numbers outside the grid show the lengths of black cell blocks in the corresponding row or column. There should be at least one white cell between two blocks.

Draw a single closed line travelling vertically or horizontally through all white cells. All cells where line crosses itself are shown. Line should visit all cells with digits in order and cannot make turn in these cells.

Appearances in the past WPCs[edit]