The other commenters are right, the time limits were a non-issue if you chose the right algorithm. It might be the difference between solving it in 30 years and

The other commenters are right, the time limits were a non-issue if you chose the right algorithm. It might be the difference between solving it in 30 years and 300ms. I'm probably misremembering that specific problem, but they were typically very easy problems, but with a huge n and some small 'gotcha' to the scenario that allowed an algorithmic or dynamic programming trick. Not realistic at all, but they were lots of fun. All of the problems weren't like that, but those were the hardest to get.