While s contains a digit, remove the leftmost digit together with the closest remaining letter to its left. Return the string after all digits have been removed. The input guarantees that a letter is available for every removal.
Example 1:
Input: s = "a"
Output: "a"Explanation: There is no digit to trigger a removal, so "a" remains.
Example 2:
Input: s = "a0"
Output: ""Explanation: Remove the digit "0" and the closest letter to its left, "a". The string becomes empty.
Example 3:
Input: s = "abc123"
Output: ""Explanation: Remove "1" with "c", then "2" with "b", and finally "3" with "a". Every character is removed.
Constraints:
1 <= s.length <= 100- Only lowercase English letters and digits occur. Every digit has an available letter to its left to remove.