feat: Add solution for LeetCode problem 125

Author: WhiteHyun

valid-palindrome/WhiteHyun.swift

@@ -0,0 +1,32 @@
+//
+//  125. Valid Palindrome.swift
+//  https://leetcode.com/problems/valid-palindrome/description/
+//  Algorithm
+//
+//  Created by 홍승현 on 2024/04/26.
+//
+
+import Foundation
+
+final class LeetCode125 {
+  func isPalindrome(_ s: String) -> Bool {
+    if let regex = try? NSRegularExpression(pattern: "[a-zA-Z0-9]+") {
+      let string = regex
+        .matches(in: s, range: .init(location: 0, length: s.count))
+        .map { s[Range($0.range, in: s)!].lowercased() }
+        .joined()
+
+      return string == String(string.reversed())
+    }
+
+    return false
+  }
+
+  func isPalindromeUsingRegexString(_ s: String) -> Bool {
+    var alphabets = ""
+    for match in s.matches(of: /(?<alphabet>[a-zA-Z0-9]+)/) {
+      alphabets += match.alphabet.lowercased()
+    }
+    return String(alphabets.reversed()) == alphabets
+  }
+}