Thread a rope in each region. A rope is a path that passes through all cells of the region, between two cells that are end-points. End-points do not touch each other, even diagonally, even across regions.
(Rules and example from WPC 2017 IB)
History of the puzzle
Invented by Prasanna Seshadri (India) in 2017. First appeared on WPC 2017/Round 17, an innovatives round. The name Rassi Silai (रस्सी सिलाई) means "rope stitch" in Hindi.
Appearances in the past WPCs
- WPC 2017/Round 18 by Prasanna Seshadri