I've been doing a few AHC's (Atcoder Heuristic Contest) recently, and I really like them. So I wanted to do more, but I can't really find any heuristic-based contests.
I've looked at Google Hashcode, but most of the problems cannot be submitted to an OJ, you have to make a score-checker yourself.
Are there any other contests that I can use to practice for AHC?
I wanted to try AHC but couldn't understand what it actually is.Can you please explain shortly what it is if you don't mind?
(Taken word-for-word from the contest announcement)
You're given a problem which isn't like normal cp problems. There's no one solution that passes all test cases and gets AC. You get a score based on how good of a solution your code found.
I'll take AHC 4 as an example. You're given a list of words, and have to find a grid of letters with as many of those words in it (think of a word-search puzzle or a crossword). If your code fit 400 out of 800 words, then you'd get more points than someone else who got only 300 words.
The way you solve them varies for each person. What I do is write a brute force / naive version and try to find ways to improve it, and after that, try different approaches to see if they can do any better. See my comment on the AHC 4 announcement for more information.
The most similar is probably TopCoder Marathon Matches. Other than that, you can look at Kaggle for more general ML contests.