
Solve two independent tasks.
Task A — Fast exponentiation: Implement fastExponent(x, n) that returns x raised to the integer power n, where x is a double and n is a 32-bit signed integer. Requirements: O(log |n|) time via exponentiation by squaring; O(
Task B — Link neighbors in a perfect binary tree: Given the root of a perfect binary tree whose nodes have fields (val, left, right, next), set each node’s next pointer to its immediate right neighbor on the same level; if none, set it to null. Constraints: O(n) time, O(