3955. Valid Binary Strings With Cost Limit

You are given two integers n and k. The cost of a binary string s is defined as the sum of all indices i (0-based) such that s[i] == '1'. A binary string is considered valid if: - It does not contain two consecutive '1' characters. - Its cost is less than or equal to k. Return a list of all valid binary strings of length n in any order. Example 1: Input: n = 3, k = 1 Output: ["000","010"