Google Intern interview questions

Referred by a friend. Get email from HR pretty soon. Scheduled three crazy interviews on the same day in the next month. Three guys from different teams interviewed me. Answered two questions for each interview in the first two rounds. Only answered one in the last one. A pretty new question, some thing like search common ancestors in several DAGs.

The first question is atoi. The interviewer is nice and did not require me to consider the boundary case, e.g. Integer.MAX_VALUE, Integer.MIN_VALUE. The second question is "give a binary search tree and a target, find the closest number to the target".