Created
December 20, 2022 20:16
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def river_sizes(matrix): | |
sizes = [] | |
visited = [[False for value in row] for row in matrix] | |
for i in range(len(matrix)): | |
for j in range(len(matrix[i])): | |
if visited[i][j]: | |
continue | |
traverse_node(i, j, matrix, visited, sizes) | |
return sizes | |
def traverse_node(i, j, matrix, visited, sizes): | |
current_river_size = 0 | |
nodes_to_explore = [[i, j]] | |
while len(nodes_to_explore): | |
current_node = nodes_to_explore.pop() | |
i = current_node[0] | |
j = current_node[1] | |
if visited[i][j]: | |
continue | |
visited[i][j] = True | |
if matrix[i][j] == 0: | |
continue | |
current_river_size += 1 | |
unvisited_neighbors = get_unvisited_neighbors(i, j, matrix, visited) | |
for neighbor in unvisited_neighbors: | |
nodes_to_explore.append(neighbor) | |
if current_river_size > 0: | |
sizes.append(current_river_size) | |
def get_unvisited_neighbors(i, j, matrix, visited): | |
unvisited_neighbors = [] | |
if i > 0 and not visited[i - 1][j]: | |
unvisited_neighbors.append([i - 1, j]) | |
if i < len(matrix) - 1 and not visited[i + 1][j]: | |
unvisited_neighbors.append([i + 1, j]) | |
if j > 0 and not visited[i][j - 1]: | |
unvisited_neighbors.append([i, j - 1]) | |
if j < len(matrix[0]) - 1 and not visited[i][j + 1]: | |
unvisited_neighbors.append([i, j + 1]) | |
return unvisited_neighbors | |
m = [ | |
[1, 1, 0], | |
[1, 1, 0], | |
[0, 0, 1] | |
] | |
s = river_sizes(m) | |
print(s) |
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