Problem 5 [12 marks] Let n = 2 - 1 for some positive integer l. Suppose someone claims to hold an unsorted array A1..n) of distinct (-bit strings; thus, exactly one l-bit string does not appear in A. Suppose further that the only way we can access A is by calling the function FetchBit(i, j), which returns the j-th bit of the string Ali in O(1) time. Describe an algorithm to find the missing string in A using only O(n) calls to FetchBit. In this problem you can build additional data structures if necessary (for instance, build an array or a list containing indices of elements in A). But you can access A using the function FetchBit() only