GridWits
Easy tier Technique 2 of 31 Used by Smart Hint

Full Clue

A 4 means every edge of this cell is part of the loop — draw all four sides as lines.

How it works

  1. 1A 4 says the loop uses every one of this cell's four sides, so there is nothing left to choose.
  2. 2Draw all four. On a one-cell board that square IS the whole loop, which is why this clue can stand alone.
4
  • Edge the technique adds
Next in the ladder Clue Complete →

Once a clue already has all its required lines, every undecided side around it is an X.