#include <iostream>
#include <vector>

#define INF (1 << 29)

using namespace std;

struct grafo{
    vector < vector <int> > adj;
    vector <int> v;
    int nodos, aristas, inicial;

    void leer(){
        cin >> nodos >> aristas;

        adj.resize(nodos + 1);

        v = vector <int>((nodos + 1), INF);

        for(int i = 0; i < aristas; i++){
            int d, h;

            cin >> d >> h;

            adj[d].push_back(h);
            adj[h].push_back(d);
        }

        cin >> inicial;
    }

    bool DFS(const int &nodo, const int &color){
        v[nodo] = color;

        for(int i = 0; i < int(adj[nodo].size()); i++){
            int ady = adj[nodo][i];

            if(v[ady] == color) return false;
            else if(v[ady] == INF && !DFS(ady, ((color == 1) ? 2 : 1))) return false;
        }

        return true;
    }

    void resolver(){
        leer();

        if(DFS(inicial, 1))
            cout << "Es bicoloreable" << endl;
        else
            cout << "No es bicoloreable" << endl;
    }
};

int main()
{
    grafo g;

    g.resolver();

    return 0;
}