TASK DEFINITION: In this task, you are given an input list A. You need to extract and sort the unique digits used in the list in ascending order. Return -1 if there is no digit in the list.
PROBLEM: ['p', 't', '211', 'r', '439', 'h', 'g', 'c', '299', '371']

SOLUTION: 1, 2, 3, 4, 7, 9

PROBLEM: ['f', 'u', 'd', '51', 'w', '449', 'z', '313', '153', 'z', '319']

SOLUTION: 1, 3, 4, 5, 9

PROBLEM: ['r', 'f', '9', 'x', '433', '169']

SOLUTION:
1, 3, 4, 6, 9