You are given a sorted array where every element appears exactly twice, except for one element which appears only once. Find and return the single element that does not have a pair.
Given an array of integers, you need to add parentheses in such a way that the division expression evaluates to the maximum possible value. The division must respect the adjacency of integers in the array.
Given a rectangular wall made up of bricks with varying widths, your task is to determine the minimum number of bricks that a vertical line crosses. The line should be drawn such that it does not cross any brick’s edge, and you cannot place the line at the edges of the wall.
You are given an array nums, a permutation of numbers from [0, n-1], and for each index k, you need to build a set s[k] by repeatedly selecting elements based on the rule nums[k] -> nums[nums[k]] -> nums[nums[nums[k]]], stopping when a duplicate is found. Return the longest length of any such set s[k].
