When I press the submit button it redirects me to the problem page for which I am submitting the code for example when I try to submit solution for http://codeforces.com/contest/340/problem/D it redirects me to http://codeforces.com/contest/340/problem/D?csrf_token=[alphanumeric string of length 32]. I have tried this on edge and firefox with same results.

Can QTREE be solved using centroid decomposition. I solved QTREE5 using the method, but I am struggling to solve QTREE using the method. Problem