This problem: https://codeforces.me/contest/733/problem/E
is the exact same as this one: https://codeforces.me/contest/1936/problem/B
except the former one is like 8 years older than the latter one. The former one is rated $$$2400$$$, while the latter one is rated $$$2000$$$. Does this mean that a candidate master today would've been a grandmaster 8 years ago?