Remove every digit and the nearest non-digit character to its left, then return the remaining string.
You are given a string containing lowercase letters and digits. Process the string from left to right, and whenever you encounter a digit, remove that digit and also remove the closest character to its left that has not already been removed.
After all digits have been processed, return the remaining string.
The relative order of the characters that remain should stay the same as in the original string.
Input Format
- A single string
sconsisting of lowercase English letters and digits. - You should process the entire string according to the removal rule described above.
Output Format
- Return the final string after removing all digits and the matched characters to their left.
Constraints
1 <= s.length <= $10^{5}$scontains only lowercase English letters and digits.- There is always a valid character to remove when a digit is encountered in the intended problem setting.
Example 1
Input
s = "cb34"
Output
""
Explanation
3 removes b, 4 removes c, leaving nothing.
Example 2
Input
s = "abc"
Output
"abc"
Explanation
There are no digits, so nothing is removed.
Show 1 more example
Example 3
Input
s = "a1b2c3"
Output
""
Explanation
Each digit removes the closest remaining character to its left: 1 removes a, 2 removes b, and 3 removes c.
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