GridWits
Medium tier Technique 6 of 21 Smart Hint: Skyscrapers and Skyscrapers+

Line Consistency (≤4 Blanks)

Every way to fill this row or column's remaining heights that matches its clue was checked — a height eliminated here doesn't appear in any of them. Enough of the line was already filled in that there was not much left to weigh.

How it works

  1. 1The 2 on the left says exactly two buildings show along this row, and the 4 is already placed at the far end.
  2. 2Only two full orders survive: 3-1-2-4 and 3-2-1-4. Both show the 3 first, hide the two shorter buildings behind it, then show the 4.
  3. 3Every surviving order starts with 3, while no surviving order starts with 1 or 2. The first cell is therefore 3.
1 2 3 1 2 3 1 2 3 4 2
  • Height ruled out
Next in the ladder Naked Pair →

Two cells in a row or column share the exact same two candidate heights — remove those heights from the rest of the line.