Hi all,

Can someone help me identify the right data structure that satisfies the constraints I outlined? - Should maintain sorted order when inserting (or allow for looking up the rank and inserting in that position) - Should have efficient insertion - Should have efficient prefix sums

I think what I need is a dynamic(?) segment tree that allows insertion at arbitrary points, but unsure how I would ensure it stays balanced. Any help would be appreciated.

Some things I tried to make work

• gnu pbds as described in this post, seemed promising but does not allow me to add in the custom prefix sum logic at each node

Hi all, what are some good algorithms/concepts to learn to get better at graph problems? I can usually tackle most tree problems since most of them rely on some form of modified DFS/BFS, but struggle with anything beyond that.

Hi all, I'm getting a runtime error while trying to submit my solution for 1588C - Game with Stones which I cannot replicate on the custom invocation tab or locally in vscode. Any help debugging this would be very appreciated.

My code submission: 135533102

UPDATE: I was able to edit the logic for modifying the map to get A/C but unable to see what the issue was. New submission- 135560689

I'm getting a runtime error when i submit my code using C++ 17, but the same code is accepted for C++ 17 64 bit. I usually make all my submissions with C++17, so I'm interested in figuring out which line is causing runtime error.

Problem: https://mirror.codeforces.com/contest/1538/problem/E

RTE (C++17): https://mirror.codeforces.com/contest/1538/submission/123976702

Accepted (C++17 64bit): https://mirror.codeforces.com/contest/1538/submission/123976695