Passi risolutivi (27)
Passo 1
Hidden Singles
valore: 5.6
categoria doc: Getting_Started
1 in B5 is last in row/box
1 in E6 is last in column
1 in H1 is last in row/box
8 in B3 is last in column
8 in J1 is last in row/box
Passo 2
Hidden Singles
valore: 4.9
categoria doc: Getting_Started
1 in D8 is last in row/column/box
1 in F2 is last in row/column/box
6 in B4 is last in row/box
8 in C6 is last in column
Passo 3
Hidden Pair
valore: 45.7
categoria doc: Hidden_Candidates
Hidden Pair 4/8 in Row A, on cells {A8|A9}
- removes 5/9 from A9
Passo 4
Pointing Pairs
valore: 67.7
categoria doc: Intersection_Removal
Pair: between Box 2 and Row C:
- 3 can be removed from C8
- 3 can be removed from C9
Last candidate 2 in C8 changed to solution
Passo 5
Hidden Singles
valore: 4.1
categoria doc: Getting_Started
2 in B2 is last in row/column/box
2 in G5 is last in row
Passo 6
Line/Unit Reduction
valore: 79.2
categoria doc: Intersection_Removal
Line/Box Reduction: 3s in box 8 remove the following in the same box:
- 3 can be removed from G4
- 3 can be removed from H5
- 3 can be removed from J5
Passo 7
Line/Unit Reduction
valore: 78.1
categoria doc: Intersection_Removal
Line/Box Reduction: 5s in box 8 remove the following in the same box:
- 5 can be removed from H5
- 5 can be removed from J5
Passo 8
Line/Unit Reduction
valore: 76.5
categoria doc: Intersection_Removal
Line/Box Reduction: 7s in box 8 remove the following in the same box:
- 7 can be removed from G4
- 7 can be removed from H5
- 7 can be removed from J5
Passo 9
Rectangle Elimination
valore: 94.9
categoria doc: Rectangle_Elimination
If +5[C5] then -5[C2] forcing +5[E2] which removes all 5s from Box 5, so C5 cannot be 5
Passo 10
Rectangle Elimination
valore: 94.2
categoria doc: Rectangle_Elimination
If +6[G8] then -6[E8] forcing +6[E3] which removes all 6s from Box 7, so G8 cannot be 6
Passo 11
Hidden Singles
valore: 3.7
categoria doc: Getting_Started
6 in G1 is last in row
Passo 12
Pointing Pairs
valore: 53.6
categoria doc: Intersection_Removal
Pair: between Box 7 and Col 2:
- 3 can be removed from E2
Passo 13
XY-Chain
valore: 221.7
categoria doc: XY_Chains
length=4. This XY-Chain is continuous and one value in each cell must be the solution, so all off-chain candidates can be removed
-3[G8]+4[G8]-4[G4]+9[G4]-9[H5]+6[H5]-6[H8]+3[H8]
- 6 can be removed from H9
- 3 can be removed from E8
- 3 can be removed from H7
- 3 can be removed from H9
- 3 can be removed from J7
- 3 can be removed from J9
Passo 14
3D Medusa
valore: 268.5
categoria doc: 3D_Medusa
(RULE 5): Uncoloured candidate 7 in D3 can see coloured 7 elsewhere and an oppositely coloured 6 in its own cell. It can be removed.
(RULE 5): Uncoloured candidate 9 in E3 can see coloured 9 elsewhere and an oppositely coloured 6 in its own cell. It can be removed.
Passo 15
Naked Pair
valore: 16.6
categoria doc: Naked_Candidates
Naked Pair 4/6 on cells {D3|E3} means
- 4 can be removed from F3
Passo 16
Hidden Pair
valore: 32.5
categoria doc: Hidden_Candidates
Hidden Pair 5/7 in Row D, on cells {D1|D5}
- removes 3 from D1
- removes 3/4 from D5
Passo 17
Hidden Singles
valore: 3.2
categoria doc: Getting_Started
3 in F1 is last in column/box
Passo 18
Pointing Pairs
valore: 45.4
categoria doc: Intersection_Removal
Pair: between Box 5 and Row E:
- 3 can be removed from E7
Passo 19
Line/Unit Reduction
valore: 60
categoria doc: Intersection_Removal
Line/Box Reduction: 9s in box 1 remove the following in the same box:
- 9 can be removed from C2
Passo 20
Rectangle Elimination
valore: 74.3
categoria doc: Rectangle_Elimination
If +7[C5] then -7[D5] forcing +7[D1] which removes all 7s from Box 1, so C5 cannot be 7
Passo 21
3D Medusa
valore: 198.1
categoria doc: 3D_Medusa
(RULE 2): Two 4s in a single unit (in Row E) have the same color in cells E3 E7 - all yellow coloured candidates can be removed
Last candidate 7 in C2 changed to solution
Last candidate 7 in D1 changed to solution
Last candidate 4 in D3 changed to solution
Last candidate 5 in D5 changed to solution
Last candidate 5 in E2 changed to solution
Last candidate 6 in E3 changed to solution
Last candidate 9 in E7 changed to solution
Last candidate 9 in F3 changed to solution
Last candidate 4 in G4 changed to solution
Last candidate 3 in G8 changed to solution
Last candidate 7 in H3 changed to solution
Last candidate 9 in H5 changed to solution
Last candidate 6 in H8 changed to solution
Last candidate 6 in J5 changed to solution
Passo 22
Naked Singles
valore: 0.6
categoria doc: Getting_Started
Last candidate 7 in A5 changed to solution
Last candidate 3 in C5 changed to solution
Last candidate 3 in D7 changed to solution
Last candidate 3 in E4 changed to solution
Last candidate 7 in F4 changed to solution
Last candidate 9 in G2 changed to solution
Last candidate 7 in G6 changed to solution
Last candidate 3 in J2 changed to solution
Passo 23
Naked Singles
valore: 0.4
categoria doc: Getting_Started
Last candidate 5 in B7 changed to solution
Last candidate 6 in D9 changed to solution
Last candidate 5 in J6 changed to solution
Passo 24
Naked Singles
valore: 0.3
categoria doc: Getting_Started
Last candidate 9 in B1 changed to solution
Last candidate 9 in C9 changed to solution
Last candidate 3 in H6 changed to solution
Last candidate 2 in H7 changed to solution
Last candidate 4 in J9 changed to solution
Passo 25
Naked Singles
valore: 0.1
categoria doc: Getting_Started
Last candidate 5 in A1 changed to solution
Last candidate 8 in A9 changed to solution
Last candidate 3 in B9 changed to solution
Last candidate 5 in C4 changed to solution
Last candidate 4 in F7 changed to solution
Last candidate 5 in H9 changed to solution
Last candidate 7 in J7 changed to solution
Passo 26
Naked Singles
valore: 0
categoria doc: Getting_Started
Last candidate 9 in A4 changed to solution
Last candidate 4 in A8 changed to solution
Last candidate 8 in E8 changed to solution
Last candidate 8 in F5 changed to solution
Last candidate 2 in F9 changed to solution
Passo 27
Naked Singles
valore: 0
categoria doc: Getting_Started
Last candidate 4 in E5 changed to solution