retired from competitive programming

friends = {"school": [Humanthe2nd, PythonshellDebugwindow, yujhtheyujh, justinw_1, leiterally, RandomPerson123, polarity], "olympiads": [htoshiro, weewoo14, volcano, ostrichthattypes, vsarca, kevlu8, CubixularHelix, kuruluu]}

orz bruce, kuruluu, CubixularHelix, polarity

https://clist.by/coder/Ivan_Li/

first Python AC: bitmask moment https://dmoj.ca/src/7057028

Some of my problems

• https://dmoj.ca/problem/xdiagonal my first problem on dmoj, a bit of implementation pain
• https://dmoj.ca/problem/othscc1p4 was meant to be dp until I realized the $O(n)$ solution
• https://dmoj.ca/problem/othscc1p5 could've been a dp and bitmask problem if it had different constraints (and if I knew dp well enough back then)
• https://dmoj.ca/problem/othscc2p4 was meant to be a 15p+ data structure question but the ideas were too template
• data structure test go brrr https://dmoj.ca/contest/othscc3 editorials soon hopefully
  • p1: not data structure :(
  • p2: store the indices for each value in some data structure (eg. monotonic stack, priority queue, set)
  • p3: line sweep + set to keep track of running maximum, alternatively use a sparse seg tree or store remaining intervals in a set
  • p4: sqrt decomposition, either do it on the array itself or process values (1 to 500) in batches.
  • p5: the tree is similar to a segment tree, we can reuse some of the ideas for update and queries

Timeline

• Feb 2023: 66/75 on CCC Junior
• Dec 2023: promoted to USACO silver (724/1000)
• Feb 2024: 34/75 on CCC Senior 💀
• Jan 2025: promoted to USACO gold (778/1000)
• Feb 2025: 57/75 on CCC Senior (bruh no CCO)
• retired from competitive programming