When I was looking through submissions, I found dadadased's submission and found it extremely peculiar.

His submissions for Problem E (E — Koxia and Tree) — https://codeforces.net/contest/1770/submission/187363250

His submissions for Problem D (D — Koxia and Game) — https://codeforces.net/contest/1770/submission/187318573

His submissions for Problem C (C — Koxia and Number Theory) — https://codeforces.net/contest/1770/submission/187293457

Just to clarify, I'm not entirely sure if dadadased cheated, but I wanted to post this to spread awareness and to get confirmation that dadadased did cheat.