private static int checkEuler(Graph graph) {
		int count = 0;
		for (int i = 0; i < graph.getVertexCount(); i++) {
			if (graph.getDegree(i) % 2 == 1) {
				count++;
			}
		}

		if (count == 0) {
			Log.print(Log.system, "The graph is euler");
			return 0;
		}
		if (count == 2) {
			Log.print(Log.system, "The graph is half-euler");
			return 1;
		}
		Log.print(Log.system, "The graph is not euler");
		return 2;
	}