2026-10-21 daily answer

Step-by-step reasoning

1. Region 4 has only one safe cell left: R4C5.
2. R4C5 rules out cells in its row, column, color region, and touching neighborhood.
3. Region 5 has only one safe cell left: R5C3.
4. R5C3 rules out cells in its row, column, color region, and touching neighborhood.
5. Region 7 has only one safe cell left: R7C1.
6. R7C1 rules out cells in its row, column, color region, and touching neighborhood.
7. Region 1 has only one safe cell left: R1C2.
8. R1C2 rules out cells in its row, column, color region, and touching neighborhood.
9. Row 3 has only one safe cell left: R3C7.
10. R3C7 rules out cells in its row, column, color region, and touching neighborhood.
11. Row 2 has only one safe cell left: R2C4.
12. Row 6 has only one safe cell left: R6C6.