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point to other answer's comment section for more elegant method
Source Link
Benjamin Wang
  • 3.1k
  • 1
  • 10
  • 27

Solution with a solve path (Solve it yourself on Penpa+)

Let's construct some rules to help us solve.

  • Corner rule: in the following configuration, where * denotes no connection and denotes an unknown connection
    B
     
X * A   C
    *
    Y 

then the cells ("in the corner") must be connected, so you can draw the two line segments B-A and A-C, giving

    B
    |
X * A - C
    *
    Y 

Applying the corner rule and easy logic to the starting position gets us

(1)

1

The bottom left can only be resolved like this. Use the corner rule as well.

(2)

2

Invalid configuration rule: if there is a cell only reachable from one neighbour, then we have an invalid configuration.

Short loop avoidance rule: in the following configuration

    B
     
X   A   C
    *
    Y 

where X and C belong to the same short loop, we cannot have X-A and A-C. Therefore B-A is connected (to avoid triggering the invalid configuration rule). So

    B
    |
X   A   C
    *
    Y 

Using this, we can make some deductions.

(3) (The red segment leads to a quick contradiction and must be removed)

3

(4)

4

Connecting the red line leads to a contradiction in the top right after around 10 moves (see the comments under the other answer for a more elegant method). So we have

(5)

5

Connecting the red line leads to a contradiction in the middle right after around 11 moves. So we have

(6)

6

Connecting some obvious things (starting from the bottom) leads to

(7)

7

Avoiding a big loop on the left leads to the solution

(8)

8

Solution with a solve path (Solve it yourself on Penpa+)

Let's construct some rules to help us solve.

  • Corner rule: in the following configuration, where * denotes no connection and denotes an unknown connection
    B
     
X * A   C
    *
    Y 

then the cells ("in the corner") must be connected, so you can draw the two line segments B-A and A-C, giving

    B
    |
X * A - C
    *
    Y 

Applying the corner rule and easy logic to the starting position gets us

(1)

1

The bottom left can only be resolved like this. Use the corner rule as well.

(2)

2

Invalid configuration rule: if there is a cell only reachable from one neighbour, then we have an invalid configuration.

Short loop avoidance rule: in the following configuration

    B
     
X   A   C
    *
    Y 

where X and C belong to the same short loop, we cannot have X-A and A-C. Therefore B-A is connected (to avoid triggering the invalid configuration rule). So

    B
    |
X   A   C
    *
    Y 

Using this, we can make some deductions.

(3) (The red segment leads to a quick contradiction and must be removed)

3

(4)

4

Connecting the red line leads to a contradiction in the top right after around 10 moves. So we have

(5)

5

Connecting the red line leads to a contradiction in the middle right after around 11 moves. So we have

(6)

6

Connecting some obvious things (starting from the bottom) leads to

(7)

7

Avoiding a big loop on the left leads to the solution

(8)

8

Solution with a solve path (Solve it yourself on Penpa+)

Let's construct some rules to help us solve.

  • Corner rule: in the following configuration, where * denotes no connection and denotes an unknown connection
    B
     
X * A   C
    *
    Y 

then the cells ("in the corner") must be connected, so you can draw the two line segments B-A and A-C, giving

    B
    |
X * A - C
    *
    Y 

Applying the corner rule and easy logic to the starting position gets us

(1)

1

The bottom left can only be resolved like this. Use the corner rule as well.

(2)

2

Invalid configuration rule: if there is a cell only reachable from one neighbour, then we have an invalid configuration.

Short loop avoidance rule: in the following configuration

    B
     
X   A   C
    *
    Y 

where X and C belong to the same short loop, we cannot have X-A and A-C. Therefore B-A is connected (to avoid triggering the invalid configuration rule). So

    B
    |
X   A   C
    *
    Y 

Using this, we can make some deductions.

(3) (The red segment leads to a quick contradiction and must be removed)

3

(4)

4

Connecting the red line leads to a contradiction in the top right after around 10 moves (see the comments under the other answer for a more elegant method). So we have

(5)

5

Connecting the red line leads to a contradiction in the middle right after around 11 moves. So we have

(6)

6

Connecting some obvious things (starting from the bottom) leads to

(7)

7

Avoiding a big loop on the left leads to the solution

(8)

8

Typo oath - path
Source Link
fljx
  • 17.1k
  • 2
  • 64
  • 101

Solution with a solve oathpath (Solve it yourself on Penpa+)

Let's construct some rules to help us solve.

  • Corner rule: in the following configuration, where * denotes no connection and denotes an unknown connection
    B
     
X * A   C
    *
    Y 

then the cells ("in the corner") must be connected, so you can draw the two line segments B-A and A-C, giving

    B
    |
X * A - C
    *
    Y 

Applying the corner rule and easy logic to the starting position gets us

(1)

1

The bottom left can only be resolved like this. Use the corner rule as well.

(2)

2

Invalid configuration rule: if there is a cell only reachable from one neighbour, then we have an invalid configuration.

Short loop avoidance rule: in the following configuration

    B
     
X   A   C
    *
    Y 

where X and C belong to the same short loop, we cannot have X-A and A-C. Therefore B-A is connected (to avoid triggering the invalid configuration rule). So

    B
    |
X   A   C
    *
    Y 

Using this, we can make some deductions.

(3) (The red segment leads to a quick contradiction and must be removed)

3

(4)

4

Connecting the red line leads to a contradiction in the top right after around 10 moves. So we have

(5)

5

Connecting the red line leads to a contradiction in the middle right after around 11 moves. So we have

(6)

6

Connecting some obvious things (starting from the bottom) leads to

(7)

7

Avoiding a big loop on the left leads to the solution

(8)

8

Solution with a solve oath (Solve it yourself on Penpa+)

Let's construct some rules to help us solve.

  • Corner rule: in the following configuration, where * denotes no connection and denotes an unknown connection
    B
     
X * A   C
    *
    Y 

then the cells ("in the corner") must be connected, so you can draw the two line segments B-A and A-C, giving

    B
    |
X * A - C
    *
    Y 

Applying the corner rule and easy logic to the starting position gets us

(1)

1

The bottom left can only be resolved like this. Use the corner rule as well.

(2)

2

Invalid configuration rule: if there is a cell only reachable from one neighbour, then we have an invalid configuration.

Short loop avoidance rule: in the following configuration

    B
     
X   A   C
    *
    Y 

where X and C belong to the same short loop, we cannot have X-A and A-C. Therefore B-A is connected (to avoid triggering the invalid configuration rule). So

    B
    |
X   A   C
    *
    Y 

Using this, we can make some deductions.

(3) (The red segment leads to a quick contradiction and must be removed)

3

(4)

4

Connecting the red line leads to a contradiction in the top right after around 10 moves. So we have

(5)

5

Connecting the red line leads to a contradiction in the middle right after around 11 moves. So we have

(6)

6

Connecting some obvious things (starting from the bottom) leads to

(7)

7

Avoiding a big loop on the left leads to the solution

(8)

8

Solution with a solve path (Solve it yourself on Penpa+)

Let's construct some rules to help us solve.

  • Corner rule: in the following configuration, where * denotes no connection and denotes an unknown connection
    B
     
X * A   C
    *
    Y 

then the cells ("in the corner") must be connected, so you can draw the two line segments B-A and A-C, giving

    B
    |
X * A - C
    *
    Y 

Applying the corner rule and easy logic to the starting position gets us

(1)

1

The bottom left can only be resolved like this. Use the corner rule as well.

(2)

2

Invalid configuration rule: if there is a cell only reachable from one neighbour, then we have an invalid configuration.

Short loop avoidance rule: in the following configuration

    B
     
X   A   C
    *
    Y 

where X and C belong to the same short loop, we cannot have X-A and A-C. Therefore B-A is connected (to avoid triggering the invalid configuration rule). So

    B
    |
X   A   C
    *
    Y 

Using this, we can make some deductions.

(3) (The red segment leads to a quick contradiction and must be removed)

3

(4)

4

Connecting the red line leads to a contradiction in the top right after around 10 moves. So we have

(5)

5

Connecting the red line leads to a contradiction in the middle right after around 11 moves. So we have

(6)

6

Connecting some obvious things (starting from the bottom) leads to

(7)

7

Avoiding a big loop on the left leads to the solution

(8)

8

Source Link
Benjamin Wang
  • 3.1k
  • 1
  • 10
  • 27

Solution with a solve oath (Solve it yourself on Penpa+)

Let's construct some rules to help us solve.

  • Corner rule: in the following configuration, where * denotes no connection and denotes an unknown connection
    B
     
X * A   C
    *
    Y 

then the cells ("in the corner") must be connected, so you can draw the two line segments B-A and A-C, giving

    B
    |
X * A - C
    *
    Y 

Applying the corner rule and easy logic to the starting position gets us

(1)

1

The bottom left can only be resolved like this. Use the corner rule as well.

(2)

2

Invalid configuration rule: if there is a cell only reachable from one neighbour, then we have an invalid configuration.

Short loop avoidance rule: in the following configuration

    B
     
X   A   C
    *
    Y 

where X and C belong to the same short loop, we cannot have X-A and A-C. Therefore B-A is connected (to avoid triggering the invalid configuration rule). So

    B
    |
X   A   C
    *
    Y 

Using this, we can make some deductions.

(3) (The red segment leads to a quick contradiction and must be removed)

3

(4)

4

Connecting the red line leads to a contradiction in the top right after around 10 moves. So we have

(5)

5

Connecting the red line leads to a contradiction in the middle right after around 11 moves. So we have

(6)

6

Connecting some obvious things (starting from the bottom) leads to

(7)

7

Avoiding a big loop on the left leads to the solution

(8)

8