Fill all 9 cells with valid London bus route numbers — for example 25, N73, or P12.
Each cell must satisfy both its row label and its column label at the same time.
Every route in the grid must be unique — the same route cannot appear twice.
Colour feedback
- Green border — correct (satisfies both constraints, not a duplicate)
- Red border — wrong constraints or duplicate route
- Amber border — route not recognised (likely a typo)