Hello Everyone,
Problem
I am trying to solve this problem But stuck at some point. I used EX. Eucledian Algorithm to check whether Solution exist or not but not able to understand how to build logic to get total number of ways. Can you help me in solving this?

Hello everyone, I solving a problem using quickselect algortihm. But getting TLE for 20 % of cases. There is blog for faster quickselect algorithm but not able to uderstand it. can you help me to solve this problem?