摩天楼数独
3
5
3
1
4
2
3
2
2
2
3
1
2
3
2
3
3
3
5
1
3
9
8
7
7
2
5
6
7
3
4
5
1
8
7
4
2
6
9
3
8
7
9
5
4
6
7
4
8
5
2
4
3
1
8
5
5
1
5
2
4
2
3
2
3
4
3
2
4
4
2
1
2
4
外部线索显示从该边缘可以看到多少座'建筑物'
什么是摩天楼数独？
摩天楼数独将每个数字想象成该高度的建筑物。网格外部的线索表示从该边缘向内看可以看到多少座建筑物——一座较高的建筑物会遮挡所有较矮的建筑物。线索1表示第一座建筑物必须是9。线索9表示建筑物按严格递增顺序排列（1,2,3,4,5,6,7,8,9）。这种变体需要数独逻辑和排列推理。
一览
| 约束类型 | 外部线索 |
| 典型给定数 | 4–10 clue values |
| 难度评级 | ★★★★☆ 4/5 |
| 平均解题时间 — 简单 | 12 分钟 |
| 平均解题时间 — 中等 | 25 分钟 |
| 平均解题时间 — 困难 | 50 分钟 |
| 平均解题时间 — 专家 | 80 分钟 |
如何解摩天楼数独
| 技巧 | 它的作用 | 级别 |
|---|---|---|
| Clue 1 Forces 9 First | A visibility clue of 1 means the first building from that edge must be a 9. All shorter buildings behind it are hidden. | 高级 |
| Clue 9 Forces Ascending Order | A clue of 9 means all buildings are visible, so digits are in strictly ascending order from that edge: 1, 2, 3, 4, 5, 6, 7, 8, 9. | 高级 |
| Permutation Enumeration | For each clue value V, enumerate all permutations of 1–9 that give exactly V visible buildings. Cross-reference opposite-edge clues. | 高级 |
| 9 Always Visible | The digit 9 is always visible from either edge. The digit 8 is visible only if it appears before any 9 from that edge. | 高级 |
| Multi-Edge Constraint | Combine the clue from one edge with the opposite edge's clue. Both must be simultaneously satisfiable. | 高级 |
平均解题时间
简单
12 分钟
中等
25 分钟
困难
50 分钟
专家
80 分钟
常见问题
什么是摩天楼数独？
Skyscraper Sudoku is a variant where numbers appear outside the grid on all four sides. Each number tells you how many distinct 'buildings' (digits) are visible when looking into that row or column from that side. Taller buildings hide shorter ones behind them — a larger digit blocks any smaller digit placed further into the row.
How does visibility work in Skyscraper Sudoku?
Imagine the digits in a row as buildings of different heights. Looking from one end, you can see a building only if no taller building stands between you and it. A clue of 1 means only the first building is visible, so it must be the tallest (digit 9). A clue of 9 means all buildings are visible, so the row must be in ascending order from that side.
What do extreme clue values tell me?
A clue of 1 means the first cell from that side holds a 9 — it blocks everything else. A clue of 9 means the row or column is in strictly ascending order from that direction (1,2,3,4,5,6,7,8,9). Both are immediately actionable. Mid-range clues require enumerating valid permutations.
Is Skyscraper Sudoku harder than regular Sudoku?
Yes, generally. Skyscraper clues require enumerating valid digit permutations for each row and column, which is more combinatorially intensive than classic Sudoku elimination. Easy puzzles are accessible; hard and expert puzzles require tracking visibility across multiple rows and columns simultaneously.
What is the best first strategy for Skyscraper Sudoku?
Start with clues of 1 and 9 — they immediately fix a digit or fully determine the order of a row. Then look for clues of 2, which constrain the position of the 9 significantly. Combine skyscraper deductions with standard Sudoku box and row/column scans.
How long does Skyscraper Sudoku take to solve?
Easy puzzles take 8–20 minutes. Medium puzzles run 20–40 minutes. Hard puzzles average 40–75 minutes and expert puzzles often exceed 90 minutes. Fast solvers develop the ability to enumerate valid visibility permutations quickly without writing them all out.