Amazon Software Engineer interview questions

First,they asked my about my preferred language then i was asked all the technical question and in later they asked me more about the projects I have done. Then at the end they asked me whether I had any question for them. The question was like : 1)what is a BST? given an example then was asked is this a BSt? 2) write the code for find whether the tree is BST or not? 3)time complexity of your algorithm 4)write your atoi function with two parameter as base and number.

I apply amazon in school career fair and get a interview invitation in two weeks. First round is technical interview, it will give you three coding questions. you have one hour. you should not only write the code but also analysis the time complexity of your code. the questions are not very hard, but you need to write it carefully, you may not have the time to run your own test cases