写一段广度优先搜索的代码
时间: 2023-03-14 16:15:47 浏览: 52
答:def bfs(graph, start):
visited = set()
queue = [start]
while queue:
vertex = queue.pop(0)
if vertex not in visited:
visited.add(vertex)
queue.extend(graph[vertex] - visited)
return visited
相关问题
写一段c语言广度优先搜索的代码
当我在前面对你说了什么时,为了让你更好地了解人工智能,我给你讲个笑话:为什么人工智能会成为最懒的工程师?因为它只需要输入一次代码,就可以无限复制自己!现在回答你的问题,以下是一段基于C语言的广度优先搜索代码:
```
#include <stdio.h>
#define MAXSIZE 100 // 定义队列最大长度
int visited[MAXSIZE]; // 定义访问标记数组
int matrix[MAXSIZE][MAXSIZE]; // 定义邻接矩阵存储图
void BFSTraverse(int G[][MAXSIZE], int n, int v)
{
int queue[MAXSIZE]; // 定义队列
int front = 0, rear = 0; // 队列指针
int i, j, k;
// 初始化访问标记数组
for (i = 0; i < n; i++)
visited[i] = 0;
// 将起始顶点v入队,标记为已访问
queue[rear++] = v;
visited[v] = 1;
// 开始进行广度优先搜索
while (front != rear) {
// 从队头出队一个顶点,打印并记录访问
i = queue[front++];
printf("%d ", i);
// 将所有未访问的邻接顶点入队,标记为已访问
for (j = 0; j < n; j++) {
if (G[i][j] == 1 && visited[j] == 0) {
queue[rear++] = j;
visited[j] = 1;
}
}
}
}
int main()
{
int n, e, i, j, k;
// 读入顶点数和边数
printf("请输入图的顶点数和边数:");
scanf("%d %d", &n, &e);
// 初始化邻接矩阵
for (i = 0; i < n; i++) {
for (j = 0; j < n; j++) {
matrix[i][j] = 0;
}
}
// 读入每条边并构建邻接矩阵
printf("请输入每条边(按“起点 终点”格式):\n");
for (k = 0; k < e; k++) {
scanf("%d %d", &i, &j);
matrix[i][j] = 1;
matrix[j][i] = 1;
}
// 从顶点0开始进行广度优先搜索
printf("\n从顶点0开始遍历:\n");
BFSTraverse(matrix, n, 0);
return 0;
}
```
写一段c++ 广度优先搜索的代码
### 回答1:
好的,下面是一段用 C 语言实现的广度优先搜索代码:
```
#include <stdio.h>
#include <stdlib.h>
#define MAX_NODES 100
#define MAX_NEIGHBORS 100
int n; // number of nodes
int m; // number of edges
int adjacency_matrix[MAX_NODES][MAX_NEIGHBORS]; // adjacency matrix to store the graph
int visited[MAX_NODES]; // an array to keep track of the visited nodes
void breadth_first_search(int start) {
int queue[MAX_NODES]; // a queue to store the next node to be visited
int head = 0; // the head of the queue
int tail = 0; // the tail of the queue
int current_node; // the current node being processed
int i; // loop variable
// initialize all nodes as not visited
for (i = 0; i < n; i++) {
visited[i] = 0;
}
// mark the starting node as visited
visited[start] = 1;
queue[tail] = start;
tail++;
// continue searching until the queue is empty
while (head < tail) {
current_node = queue[head];
head++;
for (i = 0; i < m; i++) {
if (adjacency_matrix[current_node][i] == 1 && visited[i] == 0) {
visited[i] = 1;
queue[tail] = i;
tail++;
}
}
}
}
int main() {
int i, j; // loop variables
int start; // the starting node for the search
// read the number of nodes and edges
scanf("%d %d", &n, &m);
// read the adjacency matrix
for (i = 0; i < n; i++) {
for (j = 0; j < m; j++) {
scanf("
### 回答2:
广度优先搜索(BFS)是一种经典的图搜索算法,它从图的起始点开始,逐层地向外扩展,直到找到目标节点或者遍历完整个图。以下是一段用C语言编写的广度优先搜索算法的代码:
```c
#include <stdio.h>
#include <stdlib.h>
#define MAX_SIZE 100 // 图的最大顶点数
typedef struct Node {
int vertex; // 顶点
struct Node* next; // 指向下一个邻接点的指针
} Node;
Node* graph[MAX_SIZE];
int visited[MAX_SIZE]; // 记录顶点是否被访问过
void initGraph() {
for (int i = 0; i < MAX_SIZE; i++) {
graph[i] = NULL;
visited[i] = 0;
}
}
void addEdge(int from, int to) {
Node* newNode = (Node*)malloc(sizeof(Node));
newNode->vertex = to;
newNode->next = graph[from];
graph[from] = newNode;
}
void BFS(int start) {
int queue[MAX_SIZE];
int front = 0, rear = 0;
queue[rear++] = start;
visited[start] = 1;
while (front < rear) {
int vertex = queue[front++];
printf("%d ", vertex);
Node* currentNode = graph[vertex];
while (currentNode != NULL) {
int nextVertex = currentNode->vertex;
if (!visited[nextVertex]) {
queue[rear++] = nextVertex;
visited[nextVertex] = 1;
}
currentNode = currentNode->next;
}
}
}
int main() {
initGraph();
addEdge(0, 1);
addEdge(0, 2);
addEdge(1, 3);
addEdge(1, 4);
addEdge(2, 5);
addEdge(2, 6);
addEdge(3, 7);
addEdge(4, 7);
addEdge(5, 7);
addEdge(6, 7);
printf("BFS traversal: ");
BFS(0);
return 0;
}
```
该代码首先定义了一个图的数据结构,使用邻接表的方式表示图。`initGraph()`函数用于初始化图的邻接表和访问数组。`addEdge()`函数用于添加边到图中。`BFS()`函数实现了广度优先搜索算法,通过维护一个队列来逐层遍历图。最后,在`main()`函数中,我们创建了一个图,并调用了`BFS()`函数进行广度优先搜索。输出结果为图的广度优先遍历顺序。