Find the number of contiguous subarrays in a given array whose least common multiple (LCM) is equal to a target value K.

Two players alternate removing colored pieces from a line. Determine who wins if both neighbors of a piece are the same color, and players try to maximize their moves.

Design a data structure that supports insertion, deletion, and random element retrieval, all in constant time on average. You'll need to handle edge cases carefully to achieve O(1) complexity.