Passi risolutivi (26)
Passo 1
Hidden Singles
valore: 5.2
categoria doc: Getting_Started
2 in G4 is last in row
2 in H1 is last in column/box
4 in A8 is last in row/column/box
4 in D6 is last in row
4 in F2 is last in column/box
Passo 2
Hidden Singles
valore: 4.6
categoria doc: Getting_Started
2 in A5 is last in row
2 in B8 is last in column/box
2 in F6 is last in row/box
8 in C1 is last in column
Passo 3
Hidden Singles
valore: 4.3
categoria doc: Getting_Started
7 in B5 is last in column
Passo 4
Naked Singles
valore: 1.9
categoria doc: Getting_Started
Last candidate 6 in A4 changed to solution
Passo 5
Naked Pair
valore: 19
categoria doc: Naked_Candidates
Naked Pair 7/9 on cells {A1|F1} means
- 7/9 can be removed from D1
- 7 can be removed from J1
Passo 6
Naked Pair
valore: 18.2
categoria doc: Naked_Candidates
Naked Pair 1/5 on cells {H5|J5} means
- 1/5 can be removed from H4
- 1/5 can be removed from H6
- 1/5 can be removed from J6
Passo 7
Hidden Singles
valore: 3.6
categoria doc: Getting_Started
1 in J5 is last in row
Passo 8
Naked Singles
valore: 1.7
categoria doc: Getting_Started
Last candidate 5 in H5 changed to solution
Passo 9
Hidden Singles
valore: 3.4
categoria doc: Getting_Started
5 in J2 is last in row/column/box
Passo 10
Hidden Singles
valore: 3.3
categoria doc: Getting_Started
7 in J9 is last in row
Passo 11
Naked Singles
valore: 1.5
categoria doc: Getting_Started
Last candidate 9 in A9 changed to solution
Last candidate 7 in A1 changed to solution
Last candidate 9 in F1 changed to solution
Passo 12
Hidden Singles
valore: 2.7
categoria doc: Getting_Started
9 in D7 is last in column/box
Passo 13
Pointing Pairs
valore: 39.2
categoria doc: Intersection_Removal
Pair: between Box 5 and Col 4:
- 5 can be removed from B4
Passo 14
Pointing Pairs
valore: 38.4
categoria doc: Intersection_Removal
Pair: between Box 8 and Row H:
- 9 can be removed from H2
- 9 can be removed from H3
Passo 15
Line/Unit Reduction
valore: 50.1
categoria doc: Intersection_Removal
Line/Box Reduction: 8s in box 9 remove the following in the same box:
- 8 can be removed from G9
- 8 can be removed from H7
Passo 16
Rectangle Elimination
valore: 61.9
categoria doc: Rectangle_Elimination
If +3[H2] then -3[C2] forcing +3[C6] which removes all 3s from box 8, so H2 cannot be 3
Passo 17
Rectangle Elimination
valore: 61.2
categoria doc: Rectangle_Elimination
If +3[G2] then -3[E2] forcing +3[E8] which removes all 3s from box 9, so G2 cannot be 3
Passo 18
Rectangle Elimination
valore: 60.5
categoria doc: Rectangle_Elimination
If +6[G2] then -6[C2] forcing +6[C7] which removes all 6s from box 9, so G2 cannot be 6
Passo 19
X-Cycle
valore: 143.6
categoria doc: X_Cycles
X-CYCLE on 3 (Discontinuous Alternating Nice Loop, length 6):
+3[G3]-3[J1]+3[D1]-3[D9]+3[G9]-3[G3]
- Contradiction: When G3 is set to 3 the chain implies it cannot be 3 - it can be removed
Passo 20
Line/Unit Reduction
valore: 47.3
categoria doc: Intersection_Removal
Line/Box Reduction: 3s in box 9 remove the following in the same box:
- 3 can be removed from H8
Passo 21
XY-Chain
valore: 222.1
categoria doc: XY_Chains
length=7, chain ends: B4 and F3
This proves 1 is the solution at one or possibly both ends of the chain
-1[B4]+3[B4]-3[C6]+5[C6]-5[C8]+7[C8]-7[C7]+6[C7]-6[C2]+3[C2]-3[E2]+7[E2]-7[F3]+1[F3]
- 1 can be removed from F4
Passo 22
3D Medusa
valore: 182.7
categoria doc: 3D_Medusa
(RULE 5): Uncoloured candidate 3 in D3 can see coloured 3 elsewhere and an oppositely coloured 1 in its own cell. It can be removed.
(RULE 5): Uncoloured candidate 6 in B2 can see coloured 6 elsewhere and an oppositely coloured 9 in its own cell. It can be removed.
Passo 23
X-Wing
valore: 66
categoria doc: X_Wing_Strategy
(Row->Col) 3 taken off B2, based on BH34
(Row->Col) 3 taken off B6, based on BH34
(Row->Col) 3 taken off H6, based on BH34
Last candidate 9 in B2 changed to solution
Last candidate 8 in G2 changed to solution
Last candidate 3 in G8 changed to solution
Last candidate 6 in G9 changed to solution
Last candidate 1 in H7 changed to solution
Last candidate 8 in H8 changed to solution
Passo 24
Naked Singles
valore: 0.8
categoria doc: Getting_Started
Last candidate 9 in G3 changed to solution
Passo 25
Hidden Singles
valore: 1.6
categoria doc: Getting_Started
1 in F3 is last in row
3 in D9 is last in column/box
3 in E2 is last in row
Passo 26
Naked Singles
valore: 0.2
categoria doc: Getting_Started
Last candidate 6 in C2 changed to solution
Last candidate 7 in C7 changed to solution
Last candidate 5 in C8 changed to solution
Last candidate 6 in D1 changed to solution
Last candidate 7 in D3 changed to solution
Last candidate 1 in D8 changed to solution
Last candidate 7 in E8 changed to solution
Last candidate 8 in F7 changed to solution
Last candidate 5 in F9 changed to solution
Last candidate 7 in H2 changed to solution
Last candidate 3 in J1 changed to solution
Last candidate 6 in J6 changed to solution
Last candidate 3 in B3 changed to solution
Last candidate 1 in B4 changed to solution
Last candidate 5 in B6 changed to solution
Last candidate 6 in B7 changed to solution
Last candidate 8 in B9 changed to solution
Last candidate 3 in C6 changed to solution
Last candidate 5 in D4 changed to solution
Last candidate 9 in E4 changed to solution
Last candidate 1 in E6 changed to solution
Last candidate 7 in F4 changed to solution
Last candidate 6 in H3 changed to solution
Last candidate 3 in H4 changed to solution
Last candidate 9 in H6 changed to solution