Suppose we are given A, an array of size n, comprised of an increasing sequence of numbers followed immediately by a decreasing one. What is worst case time complexity of optimal algorithm to determine if a given number x is in the array?
The explanation given on the this site is confusing to me. How we can apply binary search on unsorted array?
They have provided following explanation => This is an application of Binary search, which has time complexity $Θ(log n)$ in worst case.