用Python计算两张地图中重叠岛屿数量的程序
假设我们有两个二进制矩阵mat1和mat2。这里1代表陆地,0代表水,如果有一组1(陆地)被水包围的就叫做岛。我们必须找到在mat1和mat2中存在于完全相同坐标处的岛数。
所以,如果输入像mat1=
和mat2=
那么输出将是2,因为重叠的岛屿是,
所以有两个重叠的岛屿。
示例
让我们看看以下实现以获得更好的理解-
def solve(mat1, mat2):
r = len(mat1)
c = len(mat1[0])
last_row = r - 1
last_col = c - 1
def mark(i, j):
mat1[i][j] = mat2[i][j] = 0
if i and (mat1[i - 1][j] or mat2[i - 1][j]):
mark(i - 1, j)
if j and (mat1[i][j - 1] or mat2[i][j - 1]):
mark(i, j - 1)
if j < last_col and (mat1[i][j + 1] or mat2[i][j + 1]):
mark(i, j + 1)
if i < last_row and (mat1[i + 1][j] or mat2[i + 1][j]):
mark(i + 1, j)
for i in range(r):
for j in range(c):
if mat1[i][j] != mat2[i][j]:
mark(i, j)
islands = 0
for i in range(r):
for j in range(c):
if mat1[i][j]:
islands += 1
mark(i, j)
return islands
mat1 = [
[1, 0, 1],
[1, 0, 0],
[1, 0, 1]
]
mat2 = [
[1, 0, 1],
[1, 0, 0],
[1, 0, 0]
]
print(solve(mat1, mat2))输入
[ [1, 0, 1], [1, 0, 0], [1, 0, 1] ] [ [1, 0, 1], [1, 0, 0], [1, 0, 0] ]输出结果
2