1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
E: T E: T '+' T T: F T: F '*' F F: '0' F: '1' F: '2' F: '3' F: '4' F: '5' F: '6' F: '7' F: '8' F: '9' F: '(' E ')'