I submitted a solution of the problem https://codeforces.net/contest/1367/problem/E , and I got a WA on test 6 in the submission https://codeforces.net/contest/1367/submission/91299104, since the testcase was huge, to debug it I thought of adding the condition for the specific testcase and submitted it here https://codeforces.net/contest/1367/submission/91299197 thinking that the solution might fail on a smaller string in the next testcases, but strangely it got accepted