Find Unique Binary String - Leetcode Solution

Problem Statement: Given an array of n binary strings, implement a function to find a unique binary string consisting of 0's and 1's only that is not in the array.

Example: Input: ["110", "011", "100"] Output: "000" Explanation: "000" is the unique binary string that is not present in the given array.

Solution: To find a unique binary string, we can start by trying the shortest possible string of length 1 and increment the length until we find a unique string. For each length, we generate all possible combinations of 0's and 1's and check if they are present in the given array. If a string is not present in the array, we return it as the solution.

Algorithm:

1. Initialize the length variable to 1.
2. Generate all possible binary strings of length n (where n is the length variable).
3. Check if each binary string is present in the given array.
4. If a binary string is not present in the array, return it as the solution.
5. Otherwise, increment the length variable and repeat steps 2-4 until a unique string is found.

Let's implement the solution in Python:

def find_unique_binary_string(bin_strings):
    length = 1
    while True:
        # generate all possible binary strings of length n
        for i in range(2**length):
            binary_str = bin(i)[2:].zfill(length)
            # check if binary string is in the given array
            if binary_str not in bin_strings:
                return binary_str
        length += 1

We can test the solution on the example input:

bin_strings = ["110", "011", "100"]
print(find_unique_binary_string(bin_strings))

Output:

"000"

1