dfs和bfs算法实现c++

DFS算法实现：

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

void dfs(vector<vector<int>>& graph, int start) {
    vector<bool> visited(graph.size(), false);
    stack<int> s;
    s.push(start);

    while (!s.empty()) {
        int cur = s.top();
        s.pop();

        if (!visited[cur]) {
            visited[cur] = true;
            cout << cur << " ";

            for (int i = graph[cur].size() - 1; i >= 0; i--) {
                int neighbor = graph[cur][i];
                if (!visited[neighbor]) {
                    s.push(neighbor);
                }
            }
        }
    }
}

int main() {
    vector<vector<int>> graph = {
        {1, 2},
        {0, 2, 3},
        {0, 1, 3},
        {1, 2}
    };

    dfs(graph, 0);

    return 0;
}

BFS算法实现：

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

void bfs(vector<vector<int>>& graph, int start) {
    vector<bool> visited(graph.size(), false);
    queue<int> q;
    q.push(start);

    while (!q.empty()) {
        int cur = q.front();
        q.pop();

        if (!visited[cur]) {
            visited[cur] = true;
            cout << cur << " ";

            for (int neighbor : graph[cur]) {
                if (!visited[neighbor]) {
                    q.push(neighbor);
                }
            }
        }
    }
}

int main() {
    vector<vector<int>> graph = {
        {1, 2},
        {0, 2, 3},
        {0, 1, 3},
        {1, 2}
    };

    bfs(graph, 0);

    return 0;
}