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+"""
+Question
+
+Medium
+
+Design an algorithm to encode a list of strings to a single string.
+The encoded string is then decoded back to the original list of strings.
+
+Please implement encode and decode
+
+Example 1:
+
+Input: ["neet","code","love","you"]
+
+Output:["neet","code","love","you"]
+
+Example 2:
+
+Input: ["we","say",":","yes"]
+
+Output: ["we","say",":","yes"]
+
+Constraints:
+
+    0 <= strs.length < 100
+    0 <= strs[i].length < 200
+    strs[i] contains only UTF-8 characters.
+"""
+
+from typing import Dict, List
+
+
+class Solution:
+    """
+    A class to solve string encode and decode from input list.
+    String encode and decode from the input strs: List[str] using a encode approach.
+    """
+
+    def encode(self, strs: List[str]) -> str:
+        """
+        string encode from the input strs: List[str] using a encode approach.
+
+        Args:
+            strs: List[str]: a list of strings
+
+        Returns:
+            str: a single string
+        """
+        res: str = ""
+        for s in strs:
+            res += str(len(s)) + "#" + s
+        return res
+
+    def decode(self, s: str) -> List[str]:
+        """
+        string decode from the input str: str using a encode approach.
+
+        Args:
+            s: str: a string
+
+        Returns:
+            res: List[str] a list of strings
+        """
+        res: List = []
+        i: int = 0
+
+        while i < len(s):
+            j: int = i
+            while s[j] != "#":
+                j += 1
+            length: int = int(s[i:j])
+            i = j + 1
+            j = i + length
+            res.append(s[i:j])
+            i = j
+
+        return res
+
+    def print(self, examples: Dict) -> None:
+        """
+        funciton to print the result.
+
+        Args:
+            example: Dict, a dictionary of examples
+        """
+        for name, example in examples.items():
+            res_encode = self.encode(example)
+            print(f"{name}: {res_encode}")
+            res_decode = self.decode(res_encode)
+            print(f"{name}: {res_decode}")
+
+    def main(self):
+        """
+        main function to call print function to test examples
+        """
+        examples = {
+            "ex1": ["neet", "code", "love", "you"],
+            "ex2": ["we", "say", ":", "yes"],
+            "ex3": ["I", "love", "Yejin"],
+        }
+
+        # Passing the dictionary to the print method
+        self.print(examples)
+
+
+solution = Solution()
+solution.main()
+
+
+"""
+Solution
+
+url: https://neetcode.io/problems/string-encode-and-decode
+video: https://www.youtube.com/watch?v=B1k_sxOSgv8&embeds_referring_euri=https%3A%2F%2Fneetcode.io%2F&source_ve_path=Mjg2NjY
+
+1. encode
+time: O(n)
+space: O(n)
+code:
+```python
+class Solution:
+    def encode(self, strs: List[str]) -> str:
+        res = ""
+        for s in strs:
+            res += str(len(s)) + "#" + s
+        return res
+
+    def decode(self, s: str) -> List[str]:
+        res = []
+        i = 0
+
+        while i < len(s):
+            j = i
+            while s[j] != '#':
+                j += 1
+            length = int(s[i:j])
+            i = j + 1
+            j = i + length
+            res.append(s[i:j])
+            i = j
+        return res
+```
+"""