content: public class Codec {
      public String encode(List<String> strs) {
          // Initialize a StringBuilder to hold the encoded string.
          StringBuilder encodedString = new StringBuilder();
          for (String s : strs) {
              // Append the length, the delimiter, and the string itself.
              encodedString.append(s.length()).append("/:").append(s);
          }
          return encodedString.toString();
      }
  
      public List<String> decode(String s) {
          // Initialize a list to hold the decoded strings.
          List<String> decodedStrings = new ArrayList<>();
          int i = 0;
          while (i < s.length()) {
              // Find the delimiter.
              int delim = s.indexOf("/:", i);
              // Get the length, which is before the delimiter.
              int length = Integer.parseInt(s.substring(i, delim));
              // Get the string, which is of 'length' length after the delimiter.
              String str = s.substring(delim + 2, delim + 2 + length);
              // Add the string to the list.
              decodedStrings.add(str);
              // Move the index to the start of the next length.
              i = delim + 2 + length;
          }
          return decodedStrings;
      }
  }