feat: add 0238 Encode and Decode Strings solution

Author: hyogshin

encode-and-decode-strings/hyogshin.py

@@ -0,0 +1,41 @@
+from typing import List
+class Solution:
+    """
+    @param: strs: a list of strings
+    @return: encodes a list of strings to a single string.
+    """
+    def encode(self, strs):
+      return ''.join(f'{len(s)}#{s}' for s in strs)
+
+    """
+    @param: str: A string
+    @return: decodes a single string to a list of strings
+    """
+    def decode(self, s):
+
+      ans = []
+      i = 0
+      while i < len(s):
+        j = i
+        while s[j] != '#':
+          j += 1
+        length = int(s[i:j])
+        start = j + 1
+        end = start + length
+        ans.append(s[start:end])
+        
+        i = end
+      return ans
+
+if __name__ == "__main__":
+    sol = Solution()
+
+    cases = [
+        ["abc", "a#b", "", "hello"],
+        ["", ""],                      # 빈 문자열 2개
+        ["#", "##", "###"],            # 해시 포함
+    ]
+    for arr in cases:
+        enc = sol.encode(arr)
+        dec = sol.decode(enc)
+        print(arr == dec, arr, "->", enc[:50] + ("..." if len(enc) > 50 else ""))