3174. Clear Digits

Description

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.

 

Solutions

Solution: Stack

• Time complexity: O(n)
• Space complexity: O(n)

 

JavaScript

/**
 * @param {string} s
 * @return {string}
 */
const clearDigits = function (s) {
  const stack = [];

  for (const str of s) {
    if (isNaN(str)) {
      stack.push(str);
    } else {
      stack.pop();
    }
  }

  return stack.join('');
};