Passi risolutivi (36)
Passo 1
Hidden Singles
valore: 6.2
categoria doc: Getting_Started
1 in A5 is last in column/box
4 in H4 is last in column/box
9 in E4 is last in row/box
Passo 2
Naked Singles
valore: 1
categoria doc: Getting_Started
Last candidate 2 in H8 changed to solution
Passo 3
Hidden Singles
valore: 5.5
categoria doc: Getting_Started
6 in H6 is last in row/box
Passo 4
Hidden Pair
valore: 52
categoria doc: Hidden_Candidates
Hidden Pair 4/6 in Box 1, on cells {A1|C1}
- removes 2/3/8 from A1
- removes 2/3/8 from C1
Passo 5
Pointing Pairs
valore: 76.8
categoria doc: Intersection_Removal
Pair: between Box 1 and Col 2:
- 3 can be removed from D2
- 3 can be removed from F2
- 3 can be removed from H2
Passo 6
Hidden Singles
valore: 5.1
categoria doc: Getting_Started
3 in H3 is last in row
Passo 7
Hidden Singles
valore: 4.8
categoria doc: Getting_Started
3 in E5 is last in row
3 in F1 is last in column/box
Passo 8
Hidden Singles
valore: 4.5
categoria doc: Getting_Started
3 in D8 is last in row/column/box
Passo 9
Naked Pair
valore: 21.9
categoria doc: Naked_Candidates
Naked Pair 2/8 on cells {G1|J1} means
- 2/8 can be removed from G3
- 2/8 can be removed from J2
Passo 10
Pointing Pairs
valore: 64.8
categoria doc: Intersection_Removal
Pair: between Box 9 and Col 8:
- 9 can be removed from A8
- 9 can be removed from B8
Passo 11
Rectangle Elimination
valore: 107.3
categoria doc: Rectangle_Elimination
If +7[F2] then -7[F4] forcing +7[G4] which removes all 7s from Box 7, so F2 cannot be 7
Passo 12
Aligned Pair Exclusion
valore: 597
categoria doc: Aligned_Pair_Exclusion
Some solution combinations in the two gray cells would empty at least one of the coloured cells. Removing those combinations create eliminations in the gray cells.
Pair G9 / J9 reduced from 1/5/7->1/5 and 4/5/7->4/5/7
- Pair 5/7 found in ALS {H7}
- Combinations of 1/4/9 found in ALS {G8,J8}
- Combinations of 2/4/6/7 found in ALS {A9,C9,E9}
Passo 13
XY-Chain
valore: 275.4
categoria doc: XY_Chains
length=4, chain ends: G3 and H7
This proves 7 is the solution at one or possibly both ends of the chain
-7[G3]+9[G3]-9[G8]+1[G8]-1[G9]+5[G9]-5[H7]+7[H7]
- 7 can be removed from H2
Last candidate 5 in H2 changed to solution
Passo 14
Naked Singles
valore: 2
categoria doc: Getting_Started
Last candidate 7 in H7 changed to solution
Passo 15
Hidden Singles
valore: 4
categoria doc: Getting_Started
7 in C9 is last in row/column/box
Passo 16
Pointing Pairs
valore: 59
categoria doc: Intersection_Removal
Pair: between Box 9 and Col 9:
- 5 can be removed from D9
Passo 17
3D Medusa
valore: 312.5
categoria doc: 3D_Medusa
(RULE 5): Uncoloured candidate 1 in D2 can see coloured 1 elsewhere and an oppositely coloured 7 in its own cell. It can be removed.
Passo 18
Hidden Singles
valore: 3.9
categoria doc: Getting_Started
1 in F2 is last in column/box
Passo 19
Pointing Pairs
valore: 56.1
categoria doc: Intersection_Removal
Pair: between Box 4 and Col 3:
- 8 can be removed from B3
Passo 20
XY-Chain
valore: 278.5
categoria doc: XY_Chains
length=5, chain ends: D6 and J9
This proves 5 is the solution at one or possibly both ends of the chain
-5[D6]+2[D6]-2[D2]+7[D2]-7[J2]+9[J2]-9[J8]+4[J8]-4[J9]+5[J9]
- 5 can be removed from J6
Passo 21
Naked Pair
valore: 18.3
categoria doc: Naked_Candidates
Naked Pair 2/8 on cells {J1|J6} means
- 2/8 can be removed from J5
Passo 22
Unique Rectangle Type 1
valore: 72.1
categoria doc: Unique_Rectangle
Uniqueness Type 1 removing 2/8 at G6 because of G1,J1,J6
Passo 23
3D Medusa
valore: 283.9
categoria doc: 3D_Medusa
(RULE 5): Uncoloured candidate 2 in D7 can see coloured 2 elsewhere and an oppositely coloured 1 in its own cell. It can be removed.
(RULE 5): Uncoloured candidate 9 in B7 can see coloured 9 elsewhere and an oppositely coloured 1 in its own cell. It can be removed.
Passo 24
Forcing Nets
valore: 139.8
categoria doc: Forcing_Nets
If B4 is not 6 then all 1s in Row D are removed so B4 must be 6
Depth: 4 len: 10
-6[B4]+6[B8]-1[B8]+1[B7]-1[D7]
-6[B4]+6[B8]-6[F8]+6[D9]-1[D9]
Last candidate 6 in B4 changed to solution
Passo 25
Hidden Singles
valore: 3.2
categoria doc: Getting_Started
5 in B6 is last in row/box
6 in C1 is last in row
Passo 26
Naked Singles
valore: 1.3
categoria doc: Getting_Started
Last candidate 4 in A1 changed to solution
Last candidate 2 in D6 changed to solution
Last candidate 3 in G6 changed to solution
Passo 27
Naked Singles
valore: 1.2
categoria doc: Getting_Started
Last candidate 7 in D2 changed to solution
Last candidate 8 in J6 changed to solution
Passo 28
Naked Singles
valore: 1
categoria doc: Getting_Started
Last candidate 9 in C6 changed to solution
Last candidate 4 in D3 changed to solution
Last candidate 2 in J1 changed to solution
Last candidate 9 in J2 changed to solution
Passo 29
Naked Singles
valore: 0.9
categoria doc: Getting_Started
Last candidate 8 in G1 changed to solution
Last candidate 7 in G3 changed to solution
Last candidate 4 in J8 changed to solution
Passo 30
Naked Singles
valore: 0.9
categoria doc: Getting_Started
Last candidate 5 in J9 changed to solution
Passo 31
Naked Singles
valore: 0.8
categoria doc: Getting_Started
Last candidate 1 in G9 changed to solution
Last candidate 7 in J5 changed to solution
Passo 32
Naked Singles
valore: 0.7
categoria doc: Getting_Started
Last candidate 6 in D9 changed to solution
Last candidate 9 in G8 changed to solution
Passo 33
Naked Singles
valore: 0.5
categoria doc: Getting_Started
Last candidate 2 in A9 changed to solution
Last candidate 5 in D5 changed to solution
Last candidate 8 in F8 changed to solution
Passo 34
Naked Singles
valore: 0.2
categoria doc: Getting_Started
Last candidate 3 in A4 changed to solution
Last candidate 6 in A8 changed to solution
Last candidate 1 in B8 changed to solution
Last candidate 1 in D7 changed to solution
Last candidate 4 in E9 changed to solution
Last candidate 2 in F3 changed to solution
Last candidate 7 in F4 changed to solution
Last candidate 6 in F5 changed to solution
Last candidate 2 in G5 changed to solution
Passo 35
Naked Singles
valore: 0.1
categoria doc: Getting_Started
Last candidate 8 in A2 changed to solution
Last candidate 9 in B3 changed to solution
Last candidate 8 in B7 changed to solution
Last candidate 2 in C4 changed to solution
Last candidate 8 in C5 changed to solution
Last candidate 8 in E3 changed to solution
Last candidate 2 in E7 changed to solution
Last candidate 5 in F7 changed to solution
Last candidate 5 in G4 changed to solution
Passo 36
Naked Singles
valore: 0
categoria doc: Getting_Started
Last candidate 9 in A7 changed to solution
Last candidate 2 in B2 changed to solution
Last candidate 3 in C2 changed to solution
Last candidate 4 in C7 changed to solution