int (Node aNode) { if (aNode instanceof NodeLevel1_0000) return 0; else if (aNode instanceof NodeLevel1_0001) return 1; else if (aNode instanceof NodeLevel1_0010) return 2; else if (aNode instanceof NodeLevel1_0011) return 3; else if (aNode instanceof NodeLevel1_0100) return 4; else if (aNode instanceof NodeLevel1_0101) return 5; else if (aNode instanceof NodeLevel1_0110) return 6; else if (aNode instanceof NodeLevel1_0111) return 7; else if (aNode instanceof NodeLevel1_1000) return 8; else if (aNode instanceof NodeLevel1_1001) return 9; else if (aNode instanceof NodeLevel1_1010) return 10; else if (aNode instanceof NodeLevel1_1011) return 11; else if (aNode instanceof NodeLevel1_1100) return 12; else if (aNode instanceof NodeLevel1_1101) return 13; else if (aNode instanceof NodeLevel1_1110) return 14; else if (aNode instanceof NodeLevel1_1111) return 15; else return -1; }