Python/matrix/count_islands_in_matrix.py
Caeden 07e991d553
Add pep8-naming to pre-commit hooks and fixes incorrect naming conventions ()
* ci(pre-commit): Add pep8-naming to `pre-commit` hooks ()

* refactor: Fix naming conventions ()

* Update arithmetic_analysis/lu_decomposition.py

Co-authored-by: Christian Clauss <cclauss@me.com>

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* refactor(lu_decomposition): Replace `NDArray` with `ArrayLike` ()

* chore: Fix naming conventions in doctests ()

* fix: Temporarily disable project euler problem 104 ()

* chore: Fix naming conventions in doctests ()

Co-authored-by: Christian Clauss <cclauss@me.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
2022-10-13 00:54:20 +02:00

38 lines
1.4 KiB
Python

# An island in matrix is a group of linked areas, all having the same value.
# This code counts number of islands in a given matrix, with including diagonal
# connections.
class Matrix: # Public class to implement a graph
def __init__(self, row: int, col: int, graph: list[list[bool]]) -> None:
self.ROW = row
self.COL = col
self.graph = graph
def is_safe(self, i: int, j: int, visited: list[list[bool]]) -> bool:
return (
0 <= i < self.ROW
and 0 <= j < self.COL
and not visited[i][j]
and self.graph[i][j]
)
def diffs(self, i: int, j: int, visited: list[list[bool]]) -> None:
# Checking all 8 elements surrounding nth element
row_nbr = [-1, -1, -1, 0, 0, 1, 1, 1] # Coordinate order
col_nbr = [-1, 0, 1, -1, 1, -1, 0, 1]
visited[i][j] = True # Make those cells visited
for k in range(8):
if self.is_safe(i + row_nbr[k], j + col_nbr[k], visited):
self.diffs(i + row_nbr[k], j + col_nbr[k], visited)
def count_islands(self) -> int: # And finally, count all islands.
visited = [[False for j in range(self.COL)] for i in range(self.ROW)]
count = 0
for i in range(self.ROW):
for j in range(self.COL):
if visited[i][j] is False and self.graph[i][j] == 1:
self.diffs(i, j, visited)
count += 1
return count