Is there any different way to solve quartile question beside my way?

Question

I mean I solved it but i don't think its the best way.
There must be a different way to it(easier way)

https://code.sololearn.com/cnQbE1ngnvra/#cpp

question link
https://www.hackerrank.com/challenges/s10-quartiles/problem

Answer 1

Yeah but i what wanted to know is, is there any way to i solve problem without using if else statements