You didn't say anything about your skill level or experience, or what level you were looking for. Interviewers are often given a target level to interview you at, and if you are not at that level you will get low marks (though better interviewers will often suggest you be hired at a lower level).
You should have a pretty good idea of how you did on each question. Did you check edge cases? Solid test coverage? Did you ask clarifying questions? How good were your answers? If the obvious answer is O(n^2) then there's an answer that is O(n log n). If the obvious answer is O(2^n) then there's an answer that is O(n^2). Look for infinite loops. Memoization. Recursion, and unrolling that recursion into a loop.
Don't get discouraged. You were just handed a study guide for your next interview in 6 months.
Remember to ask questions about the company. Even if you know the answers. An interviewee that's asking questions looks more engaged and is more likely to get more attention. I like asking questions like "What's the best/worst part of working here?" Things that it's legit to ask more than one interviewer, in case they talk and share your questions.
Acting calm and relaxed, and being able to hold a conversation helps a lot. You're not just interviewing for your ability. You're going to be part of a team, and if your interviewer can't imagine working with you, that may translate into a pass.
Learn something new. Disjoint sets are a great tool for interviews. I've taken questions that the interviewer thought was O(n^2) and solved it in O(α(n)) which grows so slowly it might as well be O(1). I boned up on proof by induction before my Google interviews and it helped carry me through.
Practice interviewing. I went on half a dozen interviews to prep for my interview at Google. I occasionally interview even if I'm not looking. I've had 10 jobs (I used to jump around a lot) and I've probably gone on well over a hundred interviews. Most were practice ones I didn't particularly care about, some were practices that turned into jobs. Very few were specific jobs I was working to get.
You might have just gotten unlucky. http://steve-yegge.blogspot.com/2008/03/get-that-job-at-goog... has a good synopsis of the stress and dejection that not getting hired holds, particularly at Google, and how you might have just happened to get the wrong interviewers.
I'm assuming you're a software engineer....
You didn't say anything about your skill level or experience, or what level you were looking for. Interviewers are often given a target level to interview you at, and if you are not at that level you will get low marks (though better interviewers will often suggest you be hired at a lower level).
You should have a pretty good idea of how you did on each question. Did you check edge cases? Solid test coverage? Did you ask clarifying questions? How good were your answers? If the obvious answer is O(n^2) then there's an answer that is O(n log n). If the obvious answer is O(2^n) then there's an answer that is O(n^2). Look for infinite loops. Memoization. Recursion, and unrolling that recursion into a loop.
Don't get discouraged. You were just handed a study guide for your next interview in 6 months.
Remember to ask questions about the company. Even if you know the answers. An interviewee that's asking questions looks more engaged and is more likely to get more attention. I like asking questions like "What's the best/worst part of working here?" Things that it's legit to ask more than one interviewer, in case they talk and share your questions.
Acting calm and relaxed, and being able to hold a conversation helps a lot. You're not just interviewing for your ability. You're going to be part of a team, and if your interviewer can't imagine working with you, that may translate into a pass.
Learn something new. Disjoint sets are a great tool for interviews. I've taken questions that the interviewer thought was O(n^2) and solved it in O(α(n)) which grows so slowly it might as well be O(1). I boned up on proof by induction before my Google interviews and it helped carry me through.
Practice interviewing. I went on half a dozen interviews to prep for my interview at Google. I occasionally interview even if I'm not looking. I've had 10 jobs (I used to jump around a lot) and I've probably gone on well over a hundred interviews. Most were practice ones I didn't particularly care about, some were practices that turned into jobs. Very few were specific jobs I was working to get.
You might have just gotten unlucky. http://steve-yegge.blogspot.com/2008/03/get-that-job-at-goog... has a good synopsis of the stress and dejection that not getting hired holds, particularly at Google, and how you might have just happened to get the wrong interviewers.