I am learning DP I have solved almost all of the problems in CSES DP section. I want to solve CF problems because they are trickier. So I want you guys to help me with this by commenting the best problems which are above 1500 difficulty on DP.

Can you give me some tips to improve rating, and how to prepare for INOI. My goal is to get into the training camp this year.

Problem Name: Monsters.

There are N Monsters numbered from 1 to N , each of type Fire, Water or Grass represented by a string A of length N . When two Monsters battle each other, one of them wins according to the following rules: • A Fire Monster always defeats a Grass Monster. • A Water Monster always defeats a Fire Monster. • A Grass Monster always defeats a Water Monster. • In a battle between two Monsters of the same type, either one can win. Answer Q queries of the following form: if the Monsters Lj ...Rj are standing in a line from left to right, and repeatedly, two adjacent Monsters battle each other with the loser leaving the line, how many Monsters can be the last remaining Monster in at least one valid sequence of events?

Problem Link: Monsters

After two years I finally reached pupil on Codeforces.

I use Visual Studio Code with CPH and Thorium browser. I am just curious about what tools do you use to do competitive programming.

In the problem Swaps [problem:https://mirror.codeforces.com/problemset/problem/1573/B], my solution which is of O(n log n) time complexity is not working and giving a tle on test 2, when clearly the problem allows O(n log n) to pass. My solution: [submission:https://mirror.codeforces.com/contest/1573/submission/240104987]. Can somebody explain why this is happening. I know that there is a better solution in the editorial but why should this not pass?

Update: Fixed the problem :>