C++如何实现广度优先搜索(BFS)_C++图论算法中BFS的队列实现

const int MAXN = 1e5 + 5;
vector<int> graph[MAXN];  // 邻接表
bool visited[MAXN];        // 访问标记数组

void bfs(int start) {
    queue<int> q;
    q.push(start);
    visited[start] = true;

    while (!q.empty()) {
        int u = q.front();
        q.pop();
        cout << u << " ";  // 处理当前节点

        for (int v : graph[u]) {
            if (!visited[v]) {
                visited[v] = true;
                q.push(v);
            }
        }
    }
}

#include <iostream>
#include <vector>
#include <queue>
using namespace std;

const int MAXN = 7;
vector<int> graph[MAXN];
bool visited[MAXN];

void addEdge(int u, int v) {
    graph[u].push_back(v);
    graph[v].push_back(u);
}

void bfs(int start) {
    queue<int> q;
    q.push(start);
    visited[start] = true;

    while (!q.empty()) {
        int u = q.front();
        q.pop();
        cout << u << " ";

        for (int v : graph[u]) {
            if (!visited[v]) {
                visited[v] = true;
                q.push(v);
            }
        }
    }
}

int main() {
    addEdge(1, 2);
    addEdge(1, 3);
    addEdge(2, 4);
    addEdge(2, 5);
    addEdge(3, 6);

    bfs(1);  // 输出: 1 2 3 4 5 6
    return 0;
}