Merge pull request #2630 from kimoge/update

更新图论_卡码99&100_增加Python3版本
This commit is contained in:
程序员Carl
2024-07-22 10:06:17 +08:00
committed by GitHub
2 changed files with 144 additions and 0 deletions

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@ -192,6 +192,56 @@ int main() {
### Python
```python
from collections import deque
# 四个方向
position = [[0, 1], [1, 0], [0, -1], [-1, 0]]
def bfs(grid, visited, x, y):
"""
广度优先搜索对陆地进行标记
"""
que = deque() # 创建队列
# 标记当前节点并加入队列
visited[x][y] = True
que.append([x, y])
while que:
cur_x, cur_y = que.popleft() # 取出队首节点
for i, j in position:
next_x = cur_x + i
next_y = cur_y + j
# 下一节点下标越界,跳过
if next_x < 0 or next_x >= len(grid) or next_y < 0 or next_y >= len(grid[0]):
continue
# 下一节点是陆地且未被访问,标记节点并加入队列
if grid[next_x][next_y] == 1 and not visited[next_x][next_y]:
visited[next_x][next_y] = True
que.append([next_x, next_y])
n, m = map(int, input().split())
# 邻接矩阵
grid = []
for i in range(n):
grid.append(list(map(int, input().split())))
visited = [[False] * m for _ in range(n)] # 访问表
res = 0
for i in range(n):
for j in range(m):
if grid[i][j] == 1 and not visited[i][j]:
res += 1
bfs(grid, visited, i, j)
print(res)
```
### Go
### Rust

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@ -226,6 +226,100 @@ public:
### Python
DFS
```python
# 四个方向
position = [[0, 1], [1, 0], [0, -1], [-1, 0]]
count = 0
def dfs(grid, visited, x, y):
"""
深度优先搜索,对一整块陆地进行标记
"""
global count # 定义全局变量便于传递count值
for i, j in position:
cur_x = x + i
cur_y = y + j
# 下标越界,跳过
if cur_x < 0 or cur_x >= len(grid) or cur_y < 0 or cur_y >= len(grid[0]):
continue
if not visited[cur_x][cur_y] and grid[cur_x][cur_y] == 1:
visited[cur_x][cur_y] = True
count += 1
dfs(grid, visited, cur_x, cur_y)
n, m = map(int, input().split())
# 邻接矩阵
grid = []
for i in range(n):
grid.append(list(map(int, input().split())))
# 访问表
visited = [[False] * m for _ in range(n)]
result = 0 # 记录最终结果
for i in range(n):
for j in range(m):
if grid[i][j] == 1 and not visited[i][j]:
count = 1
visited[i][j] = True
dfs(grid, visited, i, j)
result = max(count, result)
print(result)
```
BFS
```python
from collections import deque
position = [[0, 1], [1, 0], [0, -1], [-1, 0]] # 四个方向
count = 0
def bfs(grid, visited, x, y):
"""
广度优先搜索对陆地进行标记
"""
global count # 声明全局变量
que = deque()
que.append([x, y])
while que:
cur_x, cur_y = que.popleft()
for i, j in position:
next_x = cur_x + i
next_y = cur_y + j
# 下标越界,跳过
if next_x < 0 or next_x >= len(grid) or next_y < 0 or next_y >= len(grid[0]):
continue
if grid[next_x][next_y] == 1 and not visited[next_x][next_y]:
visited[next_x][next_y] = True
count += 1
que.append([next_x, next_y])
n, m = map(int, input().split())
# 邻接矩阵
grid = []
for i in range(n):
grid.append(list(map(int, input().split())))
visited = [[False] * m for _ in range(n)] # 访问表
result = 0 # 记录最终结果
for i in range(n):
for j in range(m):
if grid[i][j] == 1 and not visited[i][j]:
count = 1
visited[i][j] = True
bfs(grid, visited, i, j)
res = max(result, count)
print(result)
```
### Go
### Rust