Hello , Recently i was trying to solve this problem 932B which was kinda tricky as it requires prefix sum to avoid TLE , it required 2d-prefix sum , so what's that and why i could need it , suggest some problems to get familiar with it.

Hello , suggest any problem (or set of problems) that can be solved using recursion and it's grid based , problems like go from s to e , or find the shortest path .... etc

Hello codeforces , a few days ago i started learning more about recursion , and i indeed tried to solve some very basic problems on it , however , when it comes to tricky problems i cannot think how to implement a recursive function to solve the problem , another thing makes me wondring is when should i implement a recursive function and when i use the iterative function, so if anyone has some ideas about the previous questions , write it below.

thanks.

Hello , when solving problems on binary search, i solve them because i know that i'm solving problems on Binary search topic , but if i come to a problem statement i don't know how or even if I should use binary search or not ... so my question is , how to make sure you're solving a binary search problem?

Hello codeforces , i just have learned the backtracking technique , i want to practice and put my hands on , i want some biggener freindly problems

Hello , Could some one please suggest a set of problems i can solve to put my hands on the "Coordinates Compression" technique ?