// graph
void BFS(int a, vector<int>& vec)
    {
        queue<int> q; q.push(a);
        vec.push_back(a);
        while(!q.empty())
        {
            int x = q.front();
            q.pop();
            cout << x << " ";

            vector<int> helper;
            for(int i = 0; i < numOfVertices; i++)
            {
                if(graph[i].front() == x)
                {
                    helper = graph[i];
                    break;
                }
            }

            int size = helper.size();
            for(int i = 0; i < size; i++)
            {
                if(!isMember(helper[i],vec))
                {
                    q.push(helper[i]);
                    vec.push_back(helper[i]);
                }
            }
        }
    }

    void DFS(int a, vector<int>& vec)
    {
        vec.push_back(a);
        cout << a << " ";

        vector<int> helper;
        for(int i = 0; i < numOfVertices; i++)
        {
            if(graph[i].front() == a)
            {
                helper = graph[i];
                break;
            }
        }
        int size = helper.size();
        for(int i = 0; i < size; i++)
        {
            if(!isMember(helper[i],vec))
            {
                DFS(helper[i],vec);
            }
        }
    }