Given a sorted array and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in order. You may assume no duplicates in the array.

Given a non-empty binary tree, find the maximum path sum. For this problem, a path is defined as any sequence of nodes from some starting node to any node in the tree along the parent-child ...

Budapest was the fastest growing European city in the 19th century and about a quarter of its population was Jewish. Jews in Eastern Europe have functioned like the canary in the mine: what happened ...