Coursework in C/C++

#include <vector>
#include <queue>
#include <iostream>

class Graph {
    int vertices;
    std::vector<std::vector<int>> adj;
public:
    Graph(int v) : vertices(v), adj(v) {}

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

    std::vector<int> bfs(int start) {
        std::vector<bool> visited(vertices, false);
        std::vector<int> order;
        std::queue<int> q;

        visited[start] = true;
        q.push(start);

        while (!q.empty()) {
            int curr = q.front();
            q.pop();
            order.push_back(curr);

            for (int neighbor : adj[curr]) {
                if (!visited[neighbor]) {
                    visited[neighbor] = true;
                    q.push(neighbor);
                }
            }
        }
        return order;
    }
};