That's frankly never going to be possible for someone like me. 10-15 minutes just sounds crazy. I'm lucky if I'm able to understand any problem well enough to g

That's frankly never going to be possible for someone like me. 10-15 minutes just sounds crazy. I'm lucky if I'm able to understand any problem well enough to get a brute force solution in under an hour. The O(n) or O(log n) they actually want, that's just going to be pure luck that I recognize one of the patterns that will let you apply that. The time constraints just make this whole thing exacerbating.