Hi. I've been taking a look at this problem from APIO 2007. I'm not really proficient at these kinds of problems (greedy + heap, possibly applications of dp?). Do any of you guys have nice problems to recommend? As you can see from my rating, I'm not that good yet so don't give me Div 1. D and E problems please...
I actually know 2 good problems on greedy + set/heap there on codeforces, but their statements are avaible only in russian (they're from technocup 2016, which is avaible only in russian locale). Do you mind using google.translate to translate them?
That's probably fine, just in case I can actually make sense of it.
Here you are.
http://mirror.codeforces.com/gym/100944/problem/D?locale=en
http://mirror.codeforces.com/gym/100950/problem/E?locale=en
Second is a bit harder than first, but ideas are almost the same :)
You can write me if you will be having troubles understanding the statements.