Freaks City

Given an integer, determine if it is a palindrome. The straightforward apprroach is to treat the input as a string and check if it reads the same forwards and backwards, which can be done in O(n) time where n is the length of the string. A more efficient approach uses polynomial hashing with O(n) time complexity. We'll implement both forward an ...

When sharding data by a non-integer primary key or a composite key (usually concatenated in to a string), developers often rely on Java's built-in String.hashCode() method to derive a hash value, which is then used for modulo-based sharding. While convenient, this approach can produce negative hash codes, leading to invalid shard numbers. Under ...