I want to manage challange on HACKERRANK (some old COCI, usaco .. -- problems), but I encounter with checker problem. If problem have more than 1 correct answer, how to write checker for that case? Could you show some examples (C++) ?

UPD0 I found that for problems with more than 1 correct answer, we must write checker like for approximation problems. Is it true? Could you show some examples (C++) ?

UPD1 hackerrank.com hasn't got a checker tab like polygon. It has only custom checker, but this checker doesn't use testlib. And this checker for approximation problems.

P.S Checker looks like this. I have no idea how to use this.

UPD2 Errichto and yeputons thank you for your help.

Recently I've learned centroid tree decomposition. And I solved QTREE5, but I can't solve QTREE4 with centroid tree decomposition. Help me with some hint please... Help ..

What do you think about it? Don't you think so?

My cat passed away...

He was a good cat.

Есть ли в codeforces красный который был серым?