Puzzle Description:

(This puzzle was recovered from the 2016 database crash. Description not available.)

#1: Wombat (wombatilim) on Mar 19, 2023 [HINT]       classify

Initial LL completes 28%.

R29: EL shows the 5 cannot go to the left of C12. While we can't determine whether the black in C13 is the 5 or the 2, we can mark C11 white either way.

C4: Given that there are single 1s in C3 and C5, and C4 is close enough to the edge to trigger any first clue in a row larger than a 1, the 7 cannot cross more than two >1 clues. The only placement where this works is in R2-8. LL.

R29: Regardless of whether the black in C13 goes into C12 or C14, R28C14 is white.

C7: EL marks R21-22 white. LL.

C7: If the bottom 4 goes into R25, R27-29 C8 are black. If the bottom 4 goes into C29 instead, the black at R26C9 goes into R25, and R27-29 C8 are still black. LL.

R23: Whichever way the 2nd 2 goes, it uses up the 2nd 1 in R21, so R21C14 is black. LL.

C19: If the 7 is placed in R21-27, it makes C22 invalid. It must go into R2-8 instead. LL.

R29: No matter how the 4 is placed, the black in R28C21 is the 2nd 1 in R28. LL.

R23: If the 2nd 2 goes into C9, it completes that column. This makes R12-14 C6 black, which in turn makes C8 invalid. Therefore the 2nd 2 in R23 must go into C11 instead. LL.

C10: The 3 can't go into R16-18 or it makes C9 invalid, so it must go into R10-12 instead. LL.

R2: Whether C27 or C28 is black, R3C27 must be black. LL, then the same logic can be repeated in R7. LL.

R17: If the 3rd 2 goes into C22, R22C22 is white. If the 2 goes into C20 instead, it pushes the 2nd 5 in R21 into C24, and R22C22 is still white. LL.

R29: EL marks C23 white. LL.

R21: Whichever way the 3 goes, it starts the 2 in R22, so R22C24 can be marked white.

LL to finish.

Found to have a unique solution by wombatilim.

Found to be solvable with moderate lookahead by wombatilim.

Goto next topic

You must register and log in to be able to participate in this discussion.