Leetcode 271. Encode and Decode Strings. Python (Easy)

Encode and Decode Strings

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.

Please implement encode and decode

Example

Example1

Input: ["lint","code","love","you"]
Output: ["lint","code","love","you"]
Explanation:
One possible encode method is: "lint:;code:;love:;you"

Example2

Input: ["we", "say", ":", "yes"]
Output: ["we", "say", ":", "yes"]
Explanation:
One possible encode method is: "we:;say:;:::;yes"

Solution :

class Solution:

    def encode(self, strs):
        ans = " "
        for s in strs:
            ans += str(len(s)) + "$" + s
        return ans

    def decode(self, str):
        ans = []
        i = 0
        
        while i < len(str):
            j = i 
            while str[j] != "$":
                j += 1
            l = int(str[i:j])

            ans.append(str[j+1:j+1+l])

            i = j + 1 + l

        return ans

Explaination :

Comments

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