1461. Check If a String Contains All Binary Codes of Size K.py

"""
Given a binary string s and an integer k, return true if every binary code of length k is a substring of s. Otherwise, return false.

Example 1:

Input: s = "00110110", k = 2
Output: true
Explanation: The binary codes of length 2 are "00", "01", "10" and "11". They can be all found as
substrings at indices 0, 1, 3 and 2 respectively.

Example 2:

Input: s = "0110", k = 1
Output: true
Explanation: The binary codes of length 1 are "0" and "1", it is clear that both exist as a substring.

Example 3:

Input: s = "0110", k = 2
Output: false
Explanation: The binary code "00" is of length 2 and does not exist in the array.


Constraints:

1 <= s.length <= 5 * 105
s[i] is either '0' or '1'.
1 <= k <= 20

"""


class Solution:
    def hasAllCodes(self, s: str, k: int) -> bool:

        codeSet = set()

        for i in range(len(s) - k + 1):
            codeSet.add(s[i:i + k])

        if len(codeSet) == pow(2, k):
            return True
        else:
            return False