Passi risolutivi (36)
Passo 1
Naked Singles
valore: 0
categoria doc: Getting_Started
Last candidate 3 in B5 changed to solution
Passo 2
Hidden Singles
valore: 6.1
categoria doc: Getting_Started
2 in C4 is last in column/box
8 in F1 is last in row/box
Passo 3
Hidden Singles
valore: 5.7
categoria doc: Getting_Started
6 in D1 is last in column/box
Passo 4
Hidden Singles
valore: 5.5
categoria doc: Getting_Started
1 in E1 is last in column/box
Passo 5
Hidden Singles
valore: 5
categoria doc: Getting_Started
9 in G6 is last in column/box
Passo 6
Hidden Pair
valore: 48.1
categoria doc: Hidden_Candidates
Hidden Pair 5/9 in Box 1, on cells {B1|B3}
- removes 2/4 from B1
- removes 2/4/8 from B3
Passo 7
Hidden Singles
valore: 4.8
categoria doc: Getting_Started
8 in A3 is last in column/box
Passo 8
Naked Pair
valore: 23
categoria doc: Naked_Candidates
Naked Pair 5/9 on cells {B3|J3} means
- 5/9 can be removed from D3
- 5 can be removed from H3
Passo 9
Naked Pair
valore: 22.6
categoria doc: Naked_Candidates
Naked Pair 2/4 on cells {D3|E2} means
- 2/4 can be removed from D2
- 4 can be removed from F2
Passo 10
Naked Pair
valore: 22.4
categoria doc: Naked_Candidates
Naked Pair 5/9 on cells {D2|F2} means
- 5 can be removed from G2
Passo 11
Hidden Pair
valore: 42.4
categoria doc: Hidden_Candidates
Hidden Pair 7/9 in Box 6, on cells {D9|F9}
- removes 1/2/3/4/5 from D9
- removes 1/4/5/6 from F9
Passo 12
Hidden Singles
valore: 4.2
categoria doc: Getting_Started
6 in F7 is last in row/box
Passo 13
Hidden Singles
valore: 3.9
categoria doc: Getting_Started
5 in D7 is last in box
5 in F2 is last in row
6 in J9 is last in row
Passo 14
Naked Singles
valore: 1.6
categoria doc: Getting_Started
Last candidate 9 in D2 changed to solution
Last candidate 7 in D9 changed to solution
Last candidate 9 in F9 changed to solution
Passo 15
Hidden Singles
valore: 3.1
categoria doc: Getting_Started
8 in G4 is last in row/column/box
Passo 16
Pointing Pairs
valore: 44.6
categoria doc: Intersection_Removal
Pair: between Box 1 and Row A:
- 2 can be removed from A7
- 2 can be removed from A9
Passo 17
Pointing Pairs
valore: 44.2
categoria doc: Intersection_Removal
Pair: between Box 3 and Col 9:
- 3 can be removed from E9
Passo 18
Hidden Singles
valore: 2.9
categoria doc: Getting_Started
3 in E8 is last in row
Passo 19
Pointing Pairs
valore: 42.1
categoria doc: Intersection_Removal
Pair: between Box 8 and Row H:
- 3 can be removed from H1
Passo 20
Pointing Pairs
valore: 41.3
categoria doc: Intersection_Removal
Triple: between Box 2 and Col 6:
- 4 can be removed from D6
- 4 can be removed from F6
Passo 21
Pointing Pairs
valore: 40.4
categoria doc: Intersection_Removal
Pair: between Box 7 and Col 1:
- 7 can be removed from A1
- 7 can be removed from C1
Passo 22
Unique Rectangle Type 1
valore: 52.8
categoria doc: Unique_Rectangle
Uniqueness Type 1 removing 5/9 at J1 because of B1,B3,J3
Last candidate 7 in J1 changed to solution
Last candidate 5 in J4 changed to solution
Passo 23
Naked Singles
valore: 1.2
categoria doc: Getting_Started
Last candidate 9 in J3 changed to solution
Last candidate 5 in B3 changed to solution
Passo 24
Naked Singles
valore: 1.2
categoria doc: Getting_Started
Last candidate 9 in B1 changed to solution
Passo 25
Rectangle Elimination
valore: 57.8
categoria doc: Rectangle_Elimination
If +2[G2] then -2[G8] forcing +2[D8] which removes all 2s from box 4, so G2 cannot be 2
Passo 26
Rectangle Elimination
valore: 57.1
categoria doc: Rectangle_Elimination
If +2[H9] then -2[H3] forcing +2[D3] which removes all 2s from box 6, so H9 cannot be 2
Passo 27
Simple Colouring
valore: 111.4
categoria doc: Singles_Chains
(RULE 4): Uncoloured candidate 2 in G1 can see two different coloured candidates of 2 elsewhere.
(RULE 4): Uncoloured candidate 2 in H7 can see two different coloured candidates of 2 elsewhere.
Passo 28
Hidden Singles
valore: 2.2
categoria doc: Getting_Started
2 in B7 is last in column
Passo 29
Rectangle Elimination
valore: 53
categoria doc: Rectangle_Elimination
If +4[A2] then -4[E2] forcing +4[E9] which removes all 4s from box 3, so A2 cannot be 4
Passo 30
Simple Colouring
valore: 104.5
categoria doc: Singles_Chains
(RULE 4): Uncoloured candidate 4 in H9 can see two different coloured candidates of 4 elsewhere.
Passo 31
X-Cycle
valore: 154.7
categoria doc: X_Cycles
X-CYCLE on 4 (Discontinuous Alternating Nice Loop, length 8):
+4[A9]-4[A7]+4[H7]-4[H3]+4[D3]-4[E2]+4[E9]-4[A9]
- Contradiction: When A9 is set to 4 the chain implies it cannot be 4 - it can be removed
Passo 32
X-Cycle
valore: 152.7
categoria doc: X_Cycles
X-CYCLE on 4 (Discontinuous Alternating Nice Loop, length 8):
+4[B9]-4[A7]+4[H7]-4[H3]+4[D3]-4[E2]+4[E9]-4[B9]
- Contradiction: When B9 is set to 4 the chain implies it cannot be 4 - it can be removed
Last candidate 8 in B9 changed to solution
Passo 33
Naked Singles
valore: 0.9
categoria doc: Getting_Started
Last candidate 4 in B6 changed to solution
Last candidate 7 in A6 changed to solution
Last candidate 6 in C5 changed to solution
Last candidate 8 in C6 changed to solution
Last candidate 1 in F6 changed to solution
Last candidate 4 in F8 changed to solution
Last candidate 2 in G8 changed to solution
Last candidate 7 in H5 changed to solution
Passo 34
Naked Singles
valore: 0.5
categoria doc: Getting_Started
Last candidate 3 in D6 changed to solution
Last candidate 1 in D8 changed to solution
Last candidate 2 in E9 changed to solution
Last candidate 7 in F4 changed to solution
Last candidate 3 in H4 changed to solution
Last candidate 6 in H6 changed to solution
Last candidate 4 in D4 changed to solution
Last candidate 4 in E2 changed to solution
Last candidate 3 in G2 changed to solution
Passo 35
Naked Singles
valore: 0.2
categoria doc: Getting_Started
Last candidate 2 in A2 changed to solution
Last candidate 7 in C2 changed to solution
Last candidate 2 in D3 changed to solution
Last candidate 4 in H3 changed to solution
Last candidate 1 in H7 changed to solution
Last candidate 5 in H9 changed to solution
Last candidate 4 in A7 changed to solution
Last candidate 3 in C9 changed to solution
Last candidate 5 in G1 changed to solution
Last candidate 4 in G9 changed to solution
Last candidate 2 in H1 changed to solution
Passo 36
Naked Singles
valore: 0
categoria doc: Getting_Started
Last candidate 3 in A1 changed to solution
Last candidate 1 in A9 changed to solution
Last candidate 4 in C1 changed to solution