Sudoku Pair/Impair
9
5
4
2
6
3
1
4
4
1
8
5
6
8
7
5
2
4
1
2
4
5
7
6
4
3
9
3
9
9
6
2
3
1
3
7
6
2
Erreurs
0/3
Score
-
Temps
00:00
Progrès0%
Impair
Pair
Facile · Sudoku Pair/Impair
Changez la difficulté ci-dessus ↑
Comment jouer au Sudoku Pair/Impair
Les règles standard du Sudoku s'appliquent. Les cellules à anneau violet (impair) doivent contenir 1, 3, 5, 7 ou 9. Les cellules jaunes (pair) doivent contenir 2, 4, 6 ou 8. Un chiffre de parité erroné compte comme une erreur.
Guide complet →
Les cellules ombrées doivent contenir des chiffres impairs ; les cercles doivent contenir des chiffres pairs
Sudoku Pair / Impair Facile
Sudoku Pair / Impair Moyen
Sudoku Pair / Impair Difficile
Sudoku Pair / Impair Expert
Qu'est-ce que Sudoku Pair / Impair ?
Odd/Even Sudoku marque certaines cellules comme impaires (souvent ombrées en gris) ou paires (souvent cerclées). Les cellules impaires doivent contenir l'un des 1, 3, 5, 7, 9 et les cellules paires doivent contenir l'un des 2, 4, 6, 8. Cela réduit de moitié l'ensemble des candidats pour les cellules marquées immédiatement, créant des restrictions puissantes sans fournir de chiffres spécifiques.
En un coup d'œil
| Type de contrainte | Relations entre cellules |
| Indices typiques | 20–26 |
| Évaluation de la difficulté | ★★★☆☆ 3/5 |
| Temps de résolution moyen — Facile | 6 min |
| Temps de résolution moyen — Moyen | 14 min |
| Temps de résolution moyen — Difficile | 28 min |
| Temps de résolution moyen — Expert | 50 min |
Comment résoudre Sudoku Pair / Impair
| Technique | Ce qu'il fait | Niveau |
|---|---|---|
| Immediate Candidate Halving | Marked cells instantly reduce to 5 odd candidates (1,3,5,7,9) or 4 even candidates (2,4,6,8). Apply this before any other technique. | Avancé |
| Parity Counting per Box | Count how many odd-marked and even-marked cells are in each box to verify the digit distribution is achievable. | Avancé |
| Parity-Chain Elimination | If a row must contain exactly four even digits, and three positions are already even-marked, the fourth must come from the remaining unmarked cells. | Avancé |
| Parity X-Wing | When parity restricts a digit to exactly two rows and two columns, form a parity-based X-Wing for cross-elimination. | Avancé |
Temps de résolution moyens
Facile
6 min
Moyen
14 min
Difficile
28 min
Expert
50 min
Foire aux questions
Qu'est-ce que Odd/Even Sudoku ?
Odd/Even Sudoku is a variant where some cells are shaded to indicate whether they must hold an odd or even digit. Purple-ringed cells must hold odd digits (1, 3, 5, 7, or 9). Yellow-shaded cells must hold even digits (2, 4, 6, or 8). Standard Sudoku rules apply to all cells.
What is parity in Sudoku?
Parity refers to whether a number is odd or even. In Odd/Even Sudoku, you can immediately halve the candidate list for any shaded cell. An odd cell can only hold 1, 3, 5, 7, or 9. An even cell can only hold 2, 4, 6, or 8. Combined with row, column, and box constraints, parity constraints make early placements much faster.
How do parity markings help solving?
Shaded cells eliminate half the digit range immediately. If a row already contains three odd digits and has an odd-marked cell remaining, that cell is heavily constrained. Counting odd vs even cells in each row, column, and box often reveals hidden singles that would be invisible without the parity markings.
Is Odd/Even Sudoku harder than regular Sudoku?
At easy and medium difficulty, it is comparable to or easier than classic Sudoku because parity markings provide immediate candidate reductions. Hard and expert Odd/Even puzzles use sparser markings and fewer given digits, making them comparable in difficulty to hard classic Sudoku.
What is the best first move in Odd/Even Sudoku?
Scan each row, column, and box and count how many odd and even slots remain versus how many odd and even digits are still unplaced. When only one cell in a row can hold an odd digit, that cell must contain an odd digit from the remaining candidates — this is a parity-based hidden single.
How long does Odd/Even Sudoku take to solve?
Easy puzzles take 5–15 minutes. Medium puzzles run 15–30 minutes. Hard puzzles average 30–60 minutes and expert puzzles can take 60–90 minutes. Parity-based hidden singles are the primary acceleration technique that distinguishes fast solvers.