Guys, The Round 937 contest has just ended, yet I've been left in utmost sorrow, as I've missed completing 2 problems just out of trivial misconception. In Problem E, I didn't realised I had not yet check if all substrings all identical, which is so deplorable of me. And in Problem F, I just forgot to add number of b-type vertices left to the answer, and that led to wrong answer on test case 1790 — test 2. So, just be as careful as possible when you're taking part in a contest, because a miss is as good as a mile.