Lithium Technologies Senior Software Engineer interview questions

Half of the interviews were problem solving on a white board and the others were primarily discussing past experience

Questions from engineers: a. Find the missing integer in a random length int[] array. b. Minimize sets of batch email addresses sent to an API, preserving address ordering, do not include duplicates in a batch. c. Define a login interface for a web app that works for a single server then multiple servers d. Develop a pub/sub interface which suppresses duplicates and supports priority levels e. Describe the architecture for a product on your resume explain how each part works in detail.