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Challenges

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Challenges Longest parallel lines

Note: This challenge was underspecified and bad, and as such I would not encourage answering it in the future. Challenge You will be given a single 2D boolean array $M$. You may take its dimensi...

1 answer  ·  posted 4y ago by rak1507‭  ·  edited 3y ago by rak1507‭

Question code-golf boolean
#2: Post edited by user avatar rak1507‭ · 2021-05-30T20:32:20Z (over 3 years ago)
  • # Challenge
  • You will be given a single 2D boolean array \$M\$. You may take its dimensions as a separate argument if needed.
  • Find the longest parallel lines in the matrix.
  • Parallel lines can be vertical, horizontal, or diagonal, and there can't be a 1 anywhere between the two lines. (Imagine 0s are air, and the 1s are solid, the two lines have to be able to 'see' each other)
  • For example, in the matrix
  • ```
  • 0 1 1 1 0 0
  • 0 0 0 0 0 0
  • 0 1 1 1 1 0
  • 0 0 1 1 0 0
  • 0 0 0 0 0 0
  • ```
  • the longest parallel line is length 3.
  • If there are no parallel lines, output 0.
  • # Test Cases
  • ```
  • I:
  • 0 0 0 1
  • 0 0 0 0
  • 0 0 0 0
  • 0 1 0 0
  • O: 0
  • I:
  • 0 0 1 0 1
  • 0 1 0 1 0
  • 1 0 1 0 0
  • O: 3
  • I:
  • 0 0 1 0 1
  • 0 0 1 0 1
  • 0 0 1 1 1
  • 0 0 1 0 1
  • 0 0 1 0 1
  • O: 2
  • (The 1 in the middle is obstructing the line of sight)
  • ```
  • # Note:
  • This challenge was underspecified and bad, and as such I would not encourage answering it in the future.
  • # Challenge
  • You will be given a single 2D boolean array \$M\$. You may take its dimensions as a separate argument if needed.
  • Find the longest parallel lines in the matrix.
  • Parallel lines can be vertical, horizontal, or diagonal, and there can't be a 1 anywhere between the two lines. (Imagine 0s are air, and the 1s are solid, the two lines have to be able to 'see' each other)
  • For example, in the matrix
  • ```
  • 0 1 1 1 0 0
  • 0 0 0 0 0 0
  • 0 1 1 1 1 0
  • 0 0 1 1 0 0
  • 0 0 0 0 0 0
  • ```
  • the longest parallel line is length 3.
  • If there are no parallel lines, output 0.
  • # Test Cases
  • ```
  • I:
  • 0 0 0 1
  • 0 0 0 0
  • 0 0 0 0
  • 0 1 0 0
  • O: 0
  • I:
  • 0 0 1 0 1
  • 0 1 0 1 0
  • 1 0 1 0 0
  • O: 3
  • I:
  • 0 0 1 0 1
  • 0 0 1 0 1
  • 0 0 1 1 1
  • 0 0 1 0 1
  • 0 0 1 0 1
  • O: 2
  • (The 1 in the middle is obstructing the line of sight)
  • ```
#1: Initial revision by user avatar rak1507‭ · 2021-02-02T12:43:15Z (almost 4 years ago)
Longest parallel lines
# Challenge
You will be given a single 2D boolean array \$M\$. You may take its dimensions as a separate argument if needed.

Find the longest parallel lines in the matrix.
Parallel lines can be vertical, horizontal, or diagonal, and there can't be a 1 anywhere between the two lines. (Imagine 0s are air, and the 1s are solid, the two lines have to be able to 'see' each other)
For example, in the matrix
```
0 1 1 1 0 0
0 0 0 0 0 0
0 1 1 1 1 0 
0 0 1 1 0 0
0 0 0 0 0 0
```
the longest parallel line is length 3.
If there are no parallel lines, output 0.

# Test Cases
```
I:
0 0 0 1
0 0 0 0
0 0 0 0
0 1 0 0
O: 0
I:
0 0 1 0 1
0 1 0 1 0
1 0 1 0 0
O: 3
I:
0 0 1 0 1
0 0 1 0 1
0 0 1 1 1
0 0 1 0 1
0 0 1 0 1
O: 2
(The 1 in the middle is obstructing the line of sight)
```