Question 4 (20 marks] For each of the following problems, design an O(n log n)-time divide-and-conquer algorithm. Your answer for each of the problems must have the following three parts. First, (a) write your divide- and-conquer algorithm in pseudocode, then (b) analyze the running time of the algorithm by writing a recurrence relation, and finally (c) use any of the methods that we learned in class to solve the recurrence relation. Dlem 1. Given an input array A of n real values and a value v (where A is not necessarily sorted), your algorithm must return true if there are two distinct indices i and j such that A[i] + A[j] = 0; it must return false otherwise. olem 2. Given two n-element arrays A and B of real numbers and a value v (where none of the arrays is necessarily sorted), your algorithm must return true if there are indices i and j such that A[i] + B[j] = v; it must return false otherwise