Tripadvisor Software Developer interview questions

Went through 2 rounds of phone screening; and flew to Boston for on-site interviews (4 rounds in total). Interview questions were pretty typical. For example, how to count the number of 1's in a 32-bit integer; linked-list vs. array; find the lowest common ancestor in a BST; how to validate a binary tree is a BST. The on-site interview was not very well organized, waiting for 30 mins in the room for the interviewer to come. No lunch was provided throughout the 4+ hour interview process... got very tired and hungry...