Puzzle Copyright © Kevin Stone

**Objective / Rules**

- Complete the grid so that every row and column contains every number exactly once.
- The symbols indicate which squares are numerical neighbours (e.g. 12, 34, 21).
**Rule 1**– if there is**a symbol**, the numbers**are neighbours**(and differ by 1).**Rule 2**– if there is**NOT a symbol**, the numbers**are NOT neighbours**.