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I was asked this question in interview:

Check if a number N is a power of K.

Example: N = 32, K = 2 => True

N = 40, K = 5 => False

I wrote following code but got the feedback that, complexity could have be improved, How to improve its complexity?

def check_kth_power(n, k):
 while n%k == 0:
 n = n/k
 if n != 1:
 return False
 return True
 
print check_kth_power(128, 5)