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This thread is privately moderated by Jack Crossfire, who may elect to delete unwanted replies.
May 23, 2014, 01:34 AM
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Since Google's interviewing formula became accepted as the proven way to hire everyone, algorithm tests on have all but replaced the interview. The 1st codility test was 15 minutes for 2 problems & a total failure. Assumed it would be equivalent to programming tests in the past, but it was drastically harder, with a much clunkier interface. Thus ended any chance of ever working at Airware.

They might have actually configured it wrong, because the guy said it would be 70 minutes. The 2nd codility test felt better, but also had 60 minutes for 2 problems. There is never as much time as a real job. The trick to winning in Google's world is more about mastering the algorithm tests than being good at the job.

For codility, you have to read the instructions in the sample tests, take the sample tests or at least formulate how you would solve them, then read as many blog posts about the solutions as possible. They require passing the complexity requirement, passing all corner cases, handling the very large numbers in their entire stated range, very small numbers, very large data sets, & very small data sets. Their example data sets don't test the corner cases. Cleanliness of code doesn't matter & there isn't enough time to clean it up, anyway. Sometimes a clue is given in the problem, like the range of a variable being the size of an array, thus you should make a lookup table, or order sqrt N complexity, thus a for loop of sqrt N somewhere.

Time taken to read the instructions actually counts against the testing time. Get good at using the clunky interface & the clunky testing interface before taking a real test. Their clunky editor renders ! the same as |. Cut & paste don't always work. There's not enough time to use your own editor & copy a program from it. You have to use the given editor with test harness. It displays printf output & seems to support all the standard C library functions without any include files.

Using standard library functions like qsort is required. Looking up as much of the solution as possible on Goog is required. Changing programming languages erases everything you've done. Navigate between all the problems in the test, using the pulldown menu, before starting any one of them.

Take the test when your internet connection is fastest & use the fastest connection you can get. Night time is best. Have a backup connection, in case Comca$t goes down.

There are many Google results for sample codility problems & many people solve them just out of pure interest in algorithms. There's a community which just solves programming challenges with no practical use in mind. Suspect it's only because it's the modern interview process & translates into more money, but not for any practical reason.

Here are the 2 latest problems. Didn't save the 2 earliest problems.

Last edited by Jack Crossfire; May 29, 2014 at 12:26 AM.
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