GridWits
Medium tier Technique 11 of 31 Used by Smart Hint

Final Closure

When closing the path here satisfies every clue and accounts for the whole loop, the closing edge is a line.

How it works

  1. 1The drawn path is already one connected run. Its two open ends face each other across the highlighted gap.
  2. 2Closing that gap leaves every clue satisfied, every used dot with two lines, and no separate line outside the loop.
  3. 3So this is not a premature loop: draw the final edge to close the puzzle's one complete loop.
0 0 2 3 1 0 3 1 2 1 2 2 1 3 1 0
  • Edge on the loop
  • Edge the technique adds
  • Edge ruled out
  • Cells that establish the pattern
Next in the ladder Border 1-3 →

A 1 and 3 sharing a border dot force edges that the same pair in the board's interior would leave open.