アンチキング数独
8
2
5
1
7
4
7
4
3
5
9
1
4
5
9
7
8
2
1
6
9
6
5
4
2
7
2
9
3
5
3
6
6
3
9
5
4
1
アンチキング数独の遊び方
標準数独ルールが適用されます。追加ルール: 斜めに隣接するセル（または直交隣接）は同じ数字を共有してはなりません。チェス盤のキングは周囲8マスすべてに到達できます — それらのセルは数字を共有できません。
完全ガイド →
king's moveで離れた2つのcellsは同じdigitを含んではならない
アンチキング数独とは？
アンチキング数独は、チェスに着想を得た制約を追加します。1回のキングの移動で到達可能なセル（直交または対角に隣接）は、同じ数字を共有できません。これにより、非反復ルールが行、列、ボックスを超えて対角の隣接セルにも拡張され、グリッド全体の制約空間が大幅に強化されます。
概要
| 制約タイプ | アンチ制約 |
| 典型的な初期数字 | 22–28 |
| 難易度評価 | ★★★☆☆ 3/5 |
| 平均解答時間 — 簡単 | 5分 |
| 平均解答時間 — ミディアム | 13分 |
| 平均解答時間 — 難しい | 26分 |
| 平均解答時間 — エキスパート | 48分 |
アンチキング数独 の解き方
| テクニック | それが何をするか | レベル |
|---|---|---|
| Diagonal Exclusion | The king constraint extends the exclusion zone to all 8 neighbours including diagonals. Apply diagonal exclusions before standard row/col/box logic. | 上級 |
| Corner Restriction | Corner cells (e.g., r1c1) only have 3 king-move neighbours. Start with corners and edges to build initial placements. | 上級 |
| King-Chain Elimination | When a digit is placed, eliminate it simultaneously from all 8 surrounding cells. | 上級 |
| Parity via King's Move | In Anti-King, consecutive digits often become mutually king-move incompatible — trace valid placement paths using this property. | 上級 |
平均解答時間
簡単
5分
ミディアム
13分
難しい
26分
エキスパート
48分
よくある質問
Anti-King Sudokuとは何ですか？
Anti-King Sudoku is a variant where no two diagonally adjacent cells may contain the same digit. Combined with standard Sudoku rules (which already forbid matching digits in the same row, column, and box), this means a digit cannot appear in any of the eight cells surrounding a given cell.
Why is it called Anti-King?
The name comes from chess: a king can move to any of the eight adjacent squares (horizontally, vertically, or diagonally). The Anti-King constraint says no digit may be repeated within a king's move of any placed digit — it's the opposite of the king's reach being unrestricted.
How many cells does the anti-king constraint affect?
Each interior cell has eight neighbours (up to eight for corner and edge cells). All eight must hold different digits from the placed cell, on top of the standard uniqueness rules. Cells in the top-left to bottom-right diagonal neighbourhood are constrained in ways that standard Sudoku doesn't cover.
Is Anti-King Sudoku harder than regular Sudoku?
Easy Anti-King puzzles resolve faster than classic Sudoku because the extra diagonal constraint eliminates more candidates. Hard and expert puzzles compensate with fewer givens, and the diagonal interactions create subtle deduction chains that can be difficult to spot.
What is the best first move in Anti-King Sudoku?
Focus on corner cells first — they have the fewest anti-king neighbours (only 3 for a true corner). Then look at cells near already-placed digits and check how many of the eight neighbours already have that digit. Dense clustering of given digits often creates immediate anti-king placements.
How long does Anti-King Sudoku take to solve?
Easy puzzles take 6–15 minutes. Medium puzzles run 15–30 minutes. Hard puzzles average 30–60 minutes and expert puzzles can take 60–90 minutes. The diagonal constraint makes early progress fast but creates subtle interactions in the middle and end game.