271. Encode and Decode Strings

• use number plus "#" to counter the number of letters in word

class Codec:

    def encode(self, strs):
        res = ""
        for word in strs:
            res = res + str(len(word)) + "#" + word
        
        return res
        

    def decode(self, s):
        print(s)
        i = 0
        res = []
        while i < len(s):
            j = i
            num = ""
            while s[j] != "#":
                num = num + s[j]
                j += 1

            length = int(num)
            res.append(s[j + 1:j + length + 1])
            i = j +length + 1

        return res