Skyscraper Sudoku
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5
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9
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9
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4
Erreurs
0/3
Score
-
Temps
00:00
Progrès0%
Facile · Sudoku Skyscraper
Changez la difficulté ci-dessus ↑
Comment jouer au Sudoku Gratte-Ciel
Les règles standard du Sudoku s'appliquent. Chaque indice bleu vous indique combien de chiffres sont visibles en regardant dans la grille depuis ce bord — un chiffre n'est visible que s'il est plus grand que tous les chiffres précédents dans cette direction.
Guide complet →
Outside clues show how many 'buildings' are visible from that edge
Skyscraper Sudoku Facile
Skyscraper Sudoku Moyen
Skyscraper Sudoku Difficile
Skyscraper Sudoku Expert
Qu'est-ce que Skyscraper Sudoku ?
Le Skyscraper Sudoku imagine chaque chiffre comme un bâtiment de cette hauteur. Les indices à l'extérieur de la grille indiquent combien de bâtiments vous pouvez voir en regardant depuis ce bord vers l'intérieur — un bâtiment plus haut bloque tous les bâtiments plus bas derrière lui. Un indice de 1 signifie que le premier bâtiment doit être un 9. Un indice de 9 signifie que les bâtiments sont disposés dans un ordre strictement croissant (1,2,3,4,5,6,7,8,9). Cette variante nécessite à la fois la logique du Sudoku et le raisonnement par permutation.
En un coup d'œil
| Type de contrainte | Indices extérieurs |
| Indices typiques | 4–10 clue values |
| Évaluation de la difficulté | ★★★★☆ 4/5 |
| Temps de résolution moyen — Facile | 12 min |
| Temps de résolution moyen — Moyen | 25 min |
| Temps de résolution moyen — Difficile | 50 min |
| Temps de résolution moyen — Expert | 80 min |
Comment résoudre Skyscraper Sudoku
| Technique | Ce qu'il fait | Niveau |
|---|---|---|
| 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. | Avancé |
| 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. | Avancé |
| Permutation Enumeration | For each clue value V, enumerate all permutations of 1–9 that give exactly V visible buildings. Cross-reference opposite-edge clues. | Avancé |
| 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. | Avancé |
| Multi-Edge Constraint | Combine the clue from one edge with the opposite edge's clue. Both must be simultaneously satisfiable. | Avancé |
Temps de résolution moyens
Facile
12 min
Moyen
25 min
Difficile
50 min
Expert
80 min
Foire aux questions
Qu'est-ce que Skyscraper Sudoku ?
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.