Pipelink consists of a rectangular or square grid. The task is to draw a single continuous loop that passes through all cells. The loop must use all given sections and may cross itself in any cell. logic puzzle - logic puzzle books for adults - puzzle books logic - adult logic puzzle book - logic puzzle game - logic grid puzzle books - logic stacking puzzle - math puzzle books for adults - puzzle math - math puzzle games - math jigsaw puzzle - math puzzle book - math puzzle for adults - math puzzle adult