LeetCode in Kotlin

3174. Clear Digits

Easy

You are given a string s.

Your task is to remove all digits by doing this operation repeatedly:

• Delete the first digit and the closest non-digit character to its left.

Return the resulting string after removing all digits.

Example 1:

Input: s = “abc”

Output: “abc”

Explanation:

There is no digit in the string.

Example 2:

Input: s = “cb34”

Output: “”

Explanation:

First, we apply the operation on s[2], and s becomes "c4".

Then we apply the operation on s[1], and s becomes "".

Constraints:

• 1 <= s.length <= 100
• s consists only of lowercase English letters and digits.
• The input is generated such that it is possible to delete all digits.

Solution

class Solution {
    fun clearDigits(s: String): String {
        val result = StringBuilder()
        for (ch in s.toCharArray()) {
            if (ch in '0'..'9') {
                if (result.isNotEmpty()) {
                    result.deleteCharAt(result.length - 1)
                }
            } else {
                result.append(ch)
            }
        }
        return result.toString()
    }
}

This site is open source. Improve this page.