Just downloaded and installed CHelper v4.4.2 (Windows 10) and got this error:

java.lang.IncompatibleClassChangeError: Method 'com.intellij.openapi.roots.libraries.LibraryTable com.intellij.openapi.roots.impl.libraries.ProjectLibraryTable.getInstance(com.intellij.openapi.project.Project)' must be InterfaceMethodref constant

So, does anyone know the solution to this or has experienced this before?

Does Arrays.parallelSort() gives better performance than Arrays.sort() on codeforces?
Since parallelSort optimizes performance on multicore processors, does that work here?

6B - Кабинет президента I submitted this solution — 69647174

What I am trying to do is to start dfs starting on the first cell of the president's table. If there is another table in that cell's neighbour i call the color function which is also dfs but on the deputy's table and increase the ans (res) by 1.

I do not know what is wrong in this approach. Can anyone help?

UPD: Solved thanks to CodingKnight