Encode and Decode Strings -- LeetCode

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

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);

strs2 in Machine 2 should be the same as strs in Machine 1.

Implement the encode and decode methods.

Note:

The string may contain any possible characters out of 256 valid ascii characters. Your algorithm should be generalized enough to work on any possible characters.
Do not use class member/global/static variables to store states. Your encode and decode algorithms should be stateless.
Do not rely on any library method such as eval or serialize methods. You should implement your own encode/decode algorithm.

思路：每个字符串之前添加它的长度和一个%字符。

 class Codec {

 public:

     // Encodes a list of strings to a single string.

     string encode(vector<string>& strs) {

         string res;

         for (int i = ; i < strs.size(); i++)

             res += std::to_string(strs[i].size()) + "%" + strs[i];

         return res;

     }

     // Decodes a single string to a list of strings.

     vector<string> decode(string s) {

         vector<string> res;

         int curInd = ;

         int mark = s.find("%");

         while (mark != std::string::npos) {

             int len = std::stoi(s.substr(curInd, mark - curInd));

             if (len) res.push_back(s.substr(mark + , len));

             //in case it is an empty string

             else res.push_back("");

             curInd = mark + len + ;

             mark = s.find("%", curInd);

         }

         return res;

     }

 };

 // Your Codec object will be instantiated and called as such:

 // Codec codec;

 // codec.decode(codec.encode(strs));

巴特西

Encode and Decode Strings -- LeetCode

最新文章

热门文章