You are given the head of a singly linked list. Your task is to swap every two adjacent nodes in the list and return its head. The nodes themselves should be swapped, not just the values.
Given two integers dividend and divisor, divide dividend by divisor without using multiplication, division, or modulus operators. Truncate the result towards zero and return the quotient.
You are given an array of integers ’nums’. Find the next lexicographically greater permutation of the array. If no such permutation exists, return the smallest possible arrangement (sorted in ascending order). The result must be computed in place with no extra space.
You are given a sorted array ’nums’ which may have been rotated at an unknown pivot. Your task is to search for a target value in this rotated array. Return the index of the target if found, or -1 if not found. The solution must have a runtime complexity of O(log n).
