The K-Diverse Prefix

A prefix is defined as 'K-diverse' if the set of words that start with this prefix end in at least K distinct characters. Find the length of the longest K-diverse prefix in a given set of words. Input Format: 1. An integer K. 2. A sequence of space-separated strings. Output Format: An integer representing the length of the longest K-diverse prefix. Example: Input: 2 apple apply ball Output: 4 Explanation: The prefix 'appl' is shared by 'apple' (ends in 'e') and 'apply' (ends in 'y'). These are 2 distinct terminal characters. No longer prefix has 2 or more terminal characters.