Finding a random seed that solves a LeetCode problem (2023)

Marco Cognetta discusses his approach to solving a LeetCode problem by finding a random seed that generates a unique bitstring not present in a given list of unique bitstrings. The challenge involves generating a new bitstring of the same length as the input strings, which can be approached through various methods, including Cantor's diagonalization argument. Cognetta's method involves using a random seed influenced by the input to ensure that the generated bitstring is not already in the list. He explains the probability of randomly generating a valid answer, noting that while the odds seem low, they improve with smaller input sizes.

He details his implementation, which includes creating a deterministic hash function to generate the seed based on the input bitstrings. This function computes a value from the characters and their positions in the array. After testing various seeds, he successfully identified a seed that passed all test cases after 42 attempts. He reflects on potential improvements, such as optimizing the hash function and addressing input duplicates, which could have expedited the process. Overall, Cognetta's exploration highlights the intersection of randomness and algorithmic problem-solving in coding challenges.