Encode and Decode Strings

Design an algorithm to encodea list of stringstoa string. The encoded string is then sent over the network and is decoded back to the original list of strings.

Example

Machine 1 (sender) has the function:

string encode(vector<string> strs) {
  // ... your code
  return encoded_string;
}

Machine 2 (receiver) has the function:

vector<string> decode(string s) {
  //... your code
  return strs;
}

So Machine 1 does:

string encoded_string = encode(strs);

and Machine 2 does:

vector<string> strs2 = decode(encoded_string);

strs2in Machine 2 should be the same asstrsin Machine 1.

Implement theencodeanddecodemethods.

Note

list of string

直接加“/”分割

Code

public class Codec {

    // Encodes a list of strings to a single string.
    public String encode(List<String> strs) {
        StringBuilder sb = new StringBuilder();
            for (String s : strs) {
                sb.append(s.length()).append('/').append(s);
            }
        return sb.toString();
    }

    // Decodes a single string to a list of strings.
    public List<String> decode(String s) {
        List<String> res = new ArrayList<>();
        int i = 0;
        while (i < s.length()) {
            int pos = s.indexOf('/', i);
            int size = Integer.valueOf(s.substring(i, pos));
            res.add(s.substring(pos + 1, pos + size + 1));
            i = pos + size + 1;
        }
        return res;
    }
}

// Your Codec object will be instantiated and called as such:
// Codec codec = new Codec();
// codec.decode(codec.encode(strs));