困難數卡
一種無數字變體 — 只給出鉛筆標記，而非最終答案。從候選數集合而非已填入數字來解題。
困難 Sukaku。需要鎖定候選數和多步驟刪除鏈——密集的棋盤，沒有捷徑。
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什麼是 Sukaku？
難度
★★★☆☆
3/5
約束類型
Pencilmark Elimination
典型給定數
All candidates shown
平均解題時間（困難）
35分鐘
解題技巧：困難 等級
| 技巧 | 描述 | 等級 |
|---|---|---|
| Candidate Scanning | Start by scanning rows, columns, and boxes — any candidate appearing in only one cell in a group must be placed there. | 初學者 |
| Cross-Hatch Elimination | When a digit is placed (or reduced to one candidate), eliminate it from all cells in the same row, column, and box. | 初學者 |
| 裸單 | A cell with only one remaining candidate is a naked single — the digit is forced. In Sukaku, this happens automatically when you eliminate down to one candidate. | 中級 |
| 隱藏單一 | A candidate that appears exactly once in a row, column, or box must be placed in that cell regardless of how many other candidates that cell shows. | 中級 |
| Pair Elimination | Two cells in a group that share only the same two candidates form a naked pair — both candidates can be eliminated from all other cells in that group. | 進階 |
準備好終極測試了嗎？試試 專家 Sukaku — 數獨 上最難的謎題。
在 困難 需要掌握的技巧
- Hidden Pairs technique — Hard sukaku starts with deliberately bloated candidate lists — hidden pairs are the tool that cuts through, stripping the excess from exactly two cells per unit.
- X-Wing 技巧 — Because every candidate is visible, X-Wing rectangles can be spotted by pure pattern-reading — scan each digit's printed positions row by row for the two-and-two shape.
依難度平均解題時間
簡單
8分鐘
中等
18分鐘
困難
35分鐘
專家
62分鐘
想要規則、策略和解題步驟的完整演練嗎？
如何遊玩 Sukaku →
相關變體
殺手數獨
Another puzzle that opens with zero placed digits — cage sums replace pencilmarks as your only raw material.
拼圖數獨
Sharpens the same candidate-tracking discipline sukaku trains, with region shapes that twist your eliminations.
對角線數獨
Adds two more houses to feed your elimination engine — ideal for solvers who enjoy sukaku's systematic pruning.
常見問題 — 困難 Sukaku
還有問題？請參閱完整 Sukaku 指南.