Amazon Software Developer interview questions

campus interview, mainly focus on algorithms and data structure problems 1/ how to decide whether a tree is symmetric 2/ how to decide whether a string is symmetric 3/ decide whether a, b can be found in a array when a+b = c

I submitted my resume on University career fair in early February, and took two phone interviews by two different interviewers in March 14th. The first interviewer only asked me three programming questions, including Palindrome, Sorting and design an image scaling function. It took about 45 mins. He asked my to write the code via a shared document editor. The second interviewer asked my background, data structure questions and two programming questions, he didn't let me use any editor, he asked me to write down the code on a paper, then read it word by word. Since I am not a native speaker, I found that I was not able to pronounce some of the symbols, I had to describe some pieces of my code for him. Also 45 mins.