keep it simple stupid

[Amartaivan]

https://github.com/Altantur/algorithms/blob/master/basics/problem-34/code_cpp/change_sorted_array_solution1.cpp

we can count > chars ,. also we need some readable variable name

[Altantur Bayarsaikhan]

i is iterator
n is number of elements
changes is how many changes should be made
isn't it KISS ?
If you find some complex or misunderstood part, please reopen and let me know.