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Sandbox Mark my beacons

posted 2y ago by Razetime‭

Article code-golf matrix
#1: Initial revision by user avatar Razetime‭ · 2022-09-08T13:10:05Z (over 2 years ago)
Mark my beacons
Given a grid of numbers, mark the concentric areas around nonzero elements (beacons) decreasing from the value of the beacon till 1.

For example, here are some grids with a single beacon:

Size 1:
```
0 0 0    0 0 0
0 1 0 -> 0 1 0
0 0 0    0 0 0
```
Size 2:
```
0 0 0    1 1 1
0 2 0 -> 1 2 1
0 0 0    1 1 1
```

Size 3:
```
0 0 0 0 0    1 1 1 1 1
0 0 0 0 0    1 2 2 2 1
0 0 3 0 0 -> 1 2 3 2 1
0 0 0 0 0    1 2 2 2 1
0 0 0 0 0    1 1 1 1 1
```

## I/O

Your input is in the form of a 2D grid of integers. You can take the dimensions if needed.

- Your output can have multiple beacons of various sizes.
- If beacons overlap, you can overwrite one over the other.
- beacons can be on the edges of the grid. they will not wrap around.

## Tests

Test 1: [JSON Array](https://dzaima.github.io/paste#0i@aKNtDBgLE62IRNsAsb4BE2wqcaImlI0BC4GqKsxCbMFQsA)
```
Input:
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 4
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
2 0 0 0 0 0 0 0 0 0
0 0 0 2 0 0 1 0 0 0
0 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
Output:
0 0 0 0 0 0 1 2 3 3
0 0 0 0 0 0 1 2 3 4
0 0 0 0 0 0 1 2 3 3
1 1 0 0 0 0 1 2 2 2
2 1 1 1 1 0 1 1 1 1
1 1 1 2 1 0 1 0 0 0
0 0 1 1 1 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
```

Test 2: [JSON Array](https://dzaima.github.io/paste#0i@aKNtQxwA1jdbiiDchRYIKuwITqVtBAgTH5JnDFAgA)
```
Input:
1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 4 0 0 0 0
0 0 4 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 3 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Output:
1 1 1 1 1 1 0 1 2 2 2 2 2 1 0
2 2 2 2 2 1 0 1 2 3 3 3 2 1 0
2 3 3 3 2 1 0 1 2 3 4 3 2 1 0
2 3 4 3 2 1 0 1 2 3 3 3 2 1 0
2 3 3 3 2 1 0 1 2 2 2 2 2 1 0
2 2 2 2 2 1 0 1 1 1 1 1 1 1 0
1 1 1 1 1 1 0 0 0 0 0 0 0 0 0
1 2 2 2 1 0 0 0 0 0 0 0 0 0 0
1 2 3 2 1 0 0 0 0 0 0 0 0 0 0
1 2 2 2 1 0 0 0 0 0 0 0 0 0 0
```