Description
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 * 105s[i]is either'0'or'1'.1 <= k <= 20
Solutions
Solution 5 combines the simplicity of Solution 3 with early termination—it collects k-length substrings into a set using i <= s.length and returns true as soon as the set reaches size 2^k, avoiding unnecessary iterations once all codes are found.
Language: javascript(2026-02-23 08:53)DONE
CPU Performance58.82%
Memory Performance62.35%
/**
* @param {string} s
* @param {number} k
* @return {boolean}
*/
var hasAllCodes = function(s, k) {
const codes = new Set();
const target = 2 ** k;
for (let i = k; i <= s.length; i++) {
codes.add(s.slice(i - k, i));
if (codes.size === target) {
return true;
}
}
return false;
};