What is a bloom filter? What is symmetric and asymmetric encryption? How are username/passwords hashed in a system? Given a vector of classes containing start and end times, give the maximum number of overlapping classes and the time of max overlapping classes. Given an array of unsorted integers, find the element that splits the array so that the sum of elements to the left of the split is equal to the sum of elements to the right of the split. Do this is O(1) space and O(n) time.