Parhelion

(Published on 28. July 2025, 21:10 by mathpesto)

Rules:

Draw two loops. Each loop is orthogonal, non-intersecting, and goes through the centers of some cells. Each loop passes through every region exactly once. The two loops may not overlap each other nor turn at a shared cell; however, they may intersect perpendicularly.

Within a region, one loop passes through all moons and no suns, while the other loop passes through all suns and no moons. A loop cannot pass through the same type of clue (sun versus moon) in two consecutively visited regions.

Solve online:

Penpa+ (Note: It is recommended you go to settings and turn on "Any color can match green line/edge in solution". That way, each loop can be a different color and answer check will still work.)

SudokuPad (Note: This version does not have answer check.)

Solution code: Numbers of cells NOT visited by either loop in Column 1, then Column 2, then 3, then 4, then 5, then 6 (6 numbers)

Last changed on on 28. July 2025, 21:10

Solved by Calesch, tuturitu, jkuo7, Piatato, xxuurruuii, Dragonslayer, ddx02, JustinTucker, Christounet, Marshal on Mars, widjo, Chefofdeath, Paletron, stefliew, bernhard, kays, misko, Bobuardo da Vinci, puzzler05, Grausbert, SeveNateNine, ns08, Bellsita, sfushidahardy, Mr_tn

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