00:00
2
3
7
9
7
3
5
8
6
4
1
1
7
5
6
6
1
2
5
9
3
8
7
6
2
9
1
7
5
9
3
2025-09-27(Intermediate) Puzzles
Challenge that requires careful thought
Confirm each number gradually to understand the structure.
Tips for Solving Sudoku
- Start with squares with fewer numbers: Begin with rows, columns, or blocks that already have more numbers filled; fewer candidates make it easier to solve.
- Pencil marks (notes): For beginners, write possible numbers in small font in empty squares for reference.
- Review: If stuck, check for duplicate numbers or rule violations.
- Basic rule: Do not repeat the same number in the same row, column, or 3x3 block.