Please don't do that, we are not in 1970's C code. Variables should be declared as local as possible. You are not saving up anything and the compiler will optimize it for you anyways.

I would not use recursion in Java --> https://softwareengineering.stackexchange.com/questions/272061/why-doesnt-java-have-optimization-for-tail-recursion-at-all

It is not recommended to have recursion instead of loop in enterprise applications, because of higher memory usage, performance overhead, and in general being harder to debug/maintain.

You could declare variable c out of for, that variable will created for one times