If you get a time out then you have not passed the whole random tests. Test passed means you passed some (or one) of them but not the whole bunch.

Random tests generally represent the real difficulty (your code passing fixed tests in a reasonable amount of time doesn't guarantee it is efficient enough for the whole tests). If your receive time out and no failed test, it just means this: your code didn't return incorrect result but it times out at some time (it hasn't returned all the results it should have).