feat: Add solution for LeetCode problem 49

Author: WhiteHyun

group-anagrams/WhiteHyun.swift

@@ -0,0 +1,18 @@
+//  
+//  49. Group Anagrams
+//  https://leetcode.com/problems/group-anagrams/description/
+//  Dale-Study
+//  
+//  Created by WhiteHyun on 2024/05/19.
+//  
+
+final class Solution {
+  func groupAnagrams(_ strs: [String]) -> [[String]] {
+    var dictionary: [String: [String]] = [:]
+    for str in strs {
+      dictionary[String(str.sorted()), default: []].append(str)
+    }
+
+    return Array(dictionary.values)
+  }
+}