0 0 votes Consider a stack is implemented using an array. What is worst case time complexity of push operation? A) O(n) B) O(log n) C) O(n log n) D) O(1) Data Structures stack data-structures + – srestha 6.9k views answer comment Share Follow Print See all 18 Comments 18 18 Comments reply Show 15 previous comments srestha commented Jan 13, 2017 reply Follow flag like stack how array do deletion in O(1) time? means in array we have to go from 1st element,rt? 0 0 replyShare Rahul Jain25 commented Jan 13, 2017 reply Follow flag I will use a variable top, whenever i will insert i will insert at array[top], increment top and whenver delete i will delte array[top] , bcoz i dont need to remember how many elements are there in stack , this top variable will be doing it. Insert delete both in O(1) 0 0 replyShare Hradesh patel commented Jan 13, 2017 reply Follow flag i think here O(n) is correct 0 0 replyShare Please log in or register to add a comment.