Adjacency matrix

 #include <iostream>

    using namespace std;

    bool A[10][10];

    void initialize()
    {
        for(int i = 0;i < 10;++i)
            for(int j = 0;j < 10;++j)
                A[i][j] = false;
    }

    int main()
    {
        int x, y, nodes, edges;
        initialize();       //Since there is no edge initially
        cin >> nodes;       //Number of nodes
        cin >> edges;       //Number of edges
        for(int i = 0;i < edges;++i)
        {
            cin >> x >> y;
            A[x][y] = true;     //Mark the edges from vertex x to vertex y
       }
       if(A[3][4] == true)
          cout << "There is an edge between 3 and 4" << endl;
      else
          cout << "There is no edge between 3 and 4" << endl;

      if(A[2][3] == true)
          cout << "There is an edge between 2 and 3" << endl;
      else
          cout << "There is no edge between 2 and 3" << endl;

      return 0;
    }