define NOTVISITED 0
时间: 2024-01-03 11:04:23 浏览: 26
NOTVISITED is a constant that is usually used in graph algorithms, where it represents that a node or vertex has not yet been visited. It is typically assigned an integer value of 0 and is used to keep track of which nodes have been visited during a traversal or search of the graph.
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#include <iostream> #include <queue> using namespace std; #define MVNum 50 typedef struct { bool visited[MVNum];//辅助数组 int arcs[MVNum][MVNum];//领接矩阵 int n;// }AMGraph;//领接矩阵的结构体 AMGraph G; queue<int>Q; void BFSTraverse(int v, int n) {//v是输入的数从什么开始遍历 cout << v << " "; G.visited[v] = true; Q.push(v); int front; while (!Q.empty()) { front = Q.front();//输出队头元素 Q.pop();//弹出队头元素 for (int i = 0; i < n; i++) { if (G.arcs[front][i] != 0 && G.visited[i] == false) { cout << i << " "; G.visited[i] = true; Q.push(i); } } } } int main() { cin >> G.n; for (int i = 0; i < G.n; i++) { G.visited[i] = false; for (int j = 0; j < G.n; j++) { scanf("%d", &G.arcs[i][j]); } } BFSTraverse(0, G.n); return 0; }
好的,这是一段 C++ 代码,是一个基于邻接矩阵的图的广度优先遍历算法。
以下是转换后的 Python 代码:
```python
from collections import deque
class AMGraph:
def __init__(self, n):
self.visited = [False] * n
self.arcs = [[0] * n for _ in range(n)]
self.n = n
def BFS_traverse(v, G):
print(v, end=' ')
G.visited[v] = True
Q = deque([v])
while Q:
front = Q.popleft()
for i in range(G.n):
if G.arcs[front][i] != 0 and not G.visited[i]:
print(i, end=' ')
G.visited[i] = True
Q.append(i)
if __name__ == '__main__':
n = int(input())
G = AMGraph(n)
for i in range(n):
for j, x in enumerate(map(int, input().split())):
G.arcs[i][j] = x
BFS_traverse(0, G)
```
注意,Python 的列表下标从 0 开始,所以在 Python 代码中的数组下标要相应地减 1。另外,Python 中没有类似于 C++ 的 `scanf` 函数,可以使用 `map` 函数和 `input` 函数来读取多个整数。
错误: name 'shortest_path_count' is not defined
It seems like you are encountering a NameError in your code. This error occurs when you try to use a variable or function that is not defined in the current scope.
In this case, the error message indicates that the function `shortest_path_count` is not defined. This means that you either have not defined this function in your code or you have not imported it from another module.
To fix this error, you need to define the `shortest_path_count` function before using it in the `all_pairs_shortest_path_count` function. Alternatively, if you have defined the function in another module, you can import it using the `import` statement.
Here is an example implementation of the `shortest_path_count` function that you can use:
```
def shortest_path_count(graph, start, end):
queue = deque([(start, 1)])
count = 0
while queue:
node, dist = queue.popleft()
if node == end:
count += 1
else:
for neighbor in graph[node]:
if neighbor not in visited:
queue.append((neighbor, dist + 1))
return count
```
You can add this function to your code and call it in the `all_pairs_shortest_path_count` function to fix the error.