XV数独
5
9
3
4
3
2
5
1
7
9
4
7
4
3
6
2
5
8
6
3
5
7
4
4
8
7
3
9
3
7
2
8
6
1
3
9
2
8
XV数独の遊び方
標準の数独ルールが適用されます。隣接する2つのセルの間のXは、それらの合計が10であることを意味します。Vは合計が5であることを意味します。マーカーのないペアは、合計が10または5にならないことが保証されています。
完全ガイド →
セル間のXはそれらの合計が10であることを意味し、Vは合計が5であることを意味します
XV数独とは？
XV Sudoku（Ten-Five Sudokuとも呼ばれる）は、隣接するセルの間にXとVのマーカーを配置します。Xは2つのセルの合計が10であることを意味し、Vは合計が5であることを意味します。多くのXVパズルはnegative constraintを使用します。マーカーの欠如は、そのペアが10にも5にもならないことを保証します。標準的なSudokuと組み合わせることで、グリッド全体に非常に厳しい制約を提供します。
概要
| 制約タイプ | セルの関係 |
| 典型的な初期数字 | 18–24 |
| 難易度評価 | ★★★☆☆ 3/5 |
| 平均解答時間 — 簡単 | 8分 |
| 平均解答時間 — ミディアム | 18分 |
| 平均解答時間 — 難しい | 35分 |
| 平均解答時間 — エキスパート | 62分 |
XV数独 の解き方
| テクニック | それが何をするか | レベル |
|---|---|---|
| Negative Constraint | Where no X or V appears between adjacent cells, their sum is neither 10 nor 5. This eliminates (1,9), (2,8), (3,7), (4,6) for X and (1,4), (2,3) for V. | 上級 |
| Sum Pair Enumeration | List all digit pairs that sum to 10 (for X) or 5 (for V), then use row/column placement to identify which pair must occupy each marked pair. | 上級 |
| Marker Chain Logic | Multiple consecutive X and V markers in a row form a sum chain — enumerate valid assignments for the entire chain simultaneously. | 上級 |
| Box X-Interaction | An X pair forces both digits into specific positions within their shared box, constraining all remaining cells of that box. | 上級 |
平均解答時間
簡単
8分
ミディアム
18分
難しい
35分
エキスパート
62分
よくある質問
XV Sudokuとは何ですか？
XV Sudoku is a variant where X and V symbols appear between adjacent cells. An X marks two cells that sum to 10. A V marks two cells that sum to 5. Standard Sudoku rules apply, and — critically — all X and V relationships are fully marked: if there is no symbol between two adjacent cells, those cells are guaranteed not to sum to either 10 or 5.
What pairs sum to 10 (X)?
The valid X pairs are: 1&9, 2&8, 3&7, 4&6. Note that 5&5 sums to 10 but standard Sudoku uniqueness rules prevent two 5s from being adjacent in most cases. The X constraint immediately limits each marked cell to a small set of candidates.
What pairs sum to 5 (V)?
The valid V pairs are: 1&4, 2&3. Only four digits can ever appear in a V cell: 1, 2, 3, or 4. This makes V markers particularly powerful for restricting candidates in the lower half of the digit range.
How does the no-symbol constraint work?
All X and V relationships are shown — if two adjacent cells have no symbol, their sum is guaranteed to be neither 5 nor 10. This negative constraint eliminates candidate pairs from unmarked cell boundaries and is often as useful as the explicit symbols.
Is XV Sudoku hard to learn?
The rules are simple to memorise. The challenge is applying both the positive (X, V) and negative (no symbol) constraints simultaneously across the entire grid. Easy puzzles are very accessible; expert puzzles require exhaustive tracking of all adjacent-cell relationships.
How long does XV Sudoku take to solve?
Easy puzzles take 8–15 minutes. Medium puzzles run 15–30 minutes. Hard puzzles average 30–60 minutes and expert puzzles often exceed 90 minutes. The no-symbol negative constraint is the most time-consuming to apply systematically across a densely marked grid.