Codeforces Round #603 (Div. 2) Postmortem

Link to contest.

What went well

• I got ABCD.
• Expanding on getting ABCD, I got C and D fairly quickly, at T+36min and T+48min respectively. (Then again, D was not particularly hard, as evidenced by its 1500 rating).

What went wrong

• I didn't get A until T+1h30 and two wrong tries.
• I did not upload anything for E because my fastest solution sketches were O(NlogN), which I thought were too slow for N = 1,000,000. Turns out that O(NlogN) and a good constant factor is fine for such large N.
• I also misread E: I thought that the cursor can be moved to the left of the starting position, but the problem clearly says that it can't.

Where I got lucky

• Implementing C and D went very smoothly, taking 12min from end (open problem statement) to end (pretests passed).
• E felt approachable.