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@lesnitsky
Last active March 13, 2024 19:32
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final visited = <(int, int)>{};
Iterable<List<(int, int)>> getBiomes(List<List<int>> worldmap) sync* {
visited.clear();
for (int i = 0; i < worldmap.length; i++) {
for (int j = 0; j < worldmap[i].length; j++) {
if (visited.contains((i, j))) {
continue;
}
yield traverse(worldmap, [(i, j)]);
}
}
}
List<(int, int)> traverse(
List<List<int>> matrix,
List<(int, int)> biome,
) {
final last = biome.last;
final (x, y) = last;
visited.add((x, y));
if (x < 0 || x >= matrix.length || y < 0 || y >= matrix[x].length) {
return biome;
}
final current = matrix[x][y];
// top
if (x > 0 && matrix[x - 1][y] == current && !visited.contains((x - 1, y))) {
biome.add((x - 1, y));
traverse(matrix, biome);
}
// right
if (y < matrix[x].length - 1 &&
matrix[x][y + 1] == current &&
!visited.contains((x, y + 1))) {
biome.add((x, y + 1));
traverse(matrix, biome);
}
// bottom
if (x < matrix.length - 1 &&
matrix[x + 1][y] == current &&
!visited.contains((x + 1, y))) {
biome.add((x + 1, y));
traverse(matrix, biome);
}
// left
if (y > 0 && matrix[x][y - 1] == current && !visited.contains((x, y - 1))) {
biome.add((x, y - 1));
traverse(matrix, biome);
}
return biome;
}
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