Leetcode Problem 1064. Fixed Point

Algorithm

1. Initialize left to 0 and right to arr.length - 1.
2. Initialize answer to -1 to indicate that no fixed point has been found yet.
3. While left <= right, do the following: a. Calculate mid as (left + right) / 2. b. If arr[mid] == mid, update answer to mid and set right to mid - 1 to search for a smaller index. c. If arr[mid] < mid, set left to mid + 1. d. If arr[mid] > mid, set right to mid - 1.
4. Return answer.