O(n) because everything outside the loop is constant time and the loop runs n times given n and the input. anotherFunction does not take "input" so it would also be constant O(1). Overall, O(n)
complexity depends on anotherFunction(). if complexity of anotherFunction() is less than O(input) then compleity of funChallenge will be O(input) else complexity will be of anotherFuntion().