困難回文數獨
每個標記線上的數字前後讀取相同。每個回文鏡像其自身邏輯。
困難 回文數獨。更長的線和較少的給定數字——預期級聯回文鏈和仔細的 筆記 追蹤。
3
8
9
6
7
9
2
4
7
8
2
1
2
6
5
1
7
7
8
1
8
4
5
8
2
3
4
什麼是 回文數獨？
難度
★★★☆☆
3/5
約束類型
線條約束
典型給定數
20–28
平均解題時間（困難）
32分鐘
解題技巧：困難 等級
| 技巧 | 描述 | 等級 |
|---|---|---|
| Mirror Pair Identification | In a palindrome of length L, cell i and cell L+1−i must share the same digit. Identify all mirror pairs before solving. | 初學者 |
| Centre Cell Freedom | The central cell of an odd-length palindrome has no mirror constraint — it is only restricted by standard row/column/box rules. | 初學者 |
| Mirror Propagation | Once one cell of a mirror pair is determined, immediately set its partner to the same value. | 中級 |
| Multi-Palindrome Intersection | If two palindromes share a cell, that cell must satisfy both palindrome relationships simultaneously. | 進階 |
準備好終極測試了嗎？試試 專家 回文數獨 — 數獨 上最難的謎題。
在 困難 需要掌握的技巧
- Hidden Pairs technique — Hard palindrome grids overlap lines so a cell mirrors into two different partners — intersecting three candidate lists exposes pairs invisible to any single unit scan.
- X-Wing 技巧 — An elimination at one mirror cell exports to a distant row, so fish patterns assemble in rows the palindrome line never touches — check mirrors after every X-Wing.
依難度平均解題時間
簡單
7分鐘
中等
16分鐘
困難
32分鐘
專家
58分鐘
想要規則、策略和解題步驟的完整演練嗎？
如何遊玩 回文數獨 →
相關變體
Renban數獨
Both put structure on a drawn line's digit set — renban demands a consecutive run where palindromes demand mirror symmetry.
德式低語
Trades mirrored repetition for forced separation: adjacent line digits must differ by 5 or more.
區間數獨
Endpoint-anchored lines where position on the line carries meaning, just as it does for palindrome mirror pairs.
常見問題 — 困難 回文數獨
還有問題？請參閱完整 回文數獨指南.