The function should take a sorted array of integers and a target value as inputs, and return the index of the target value if it exists in the array, or -1 if it does not .
A.I. Evaluation of the Solution
This is a well-detailed and complete solution to the problem. The candidate has correctly identified the time and space complexity of the solution and has provided a clear explanation of the approach. The candidate has also correctly implemented a binary search algorithm to solve the problem.