wrong answer for large input

Question

I am trying to determine whether an integer can be expressed in the form of a^b where b>1 and the given integer is greater than 0. My code runs fine for all test cases except for one. It gives wrong answer for the following input: 536870912 I cant understand why.

 def isPower(self, A):
    if(A==1):
        return (1)
    for i in range(2,int(A**0.5)+1):
        val=log(A,i)
        if(int(val)-val==0):
            return (1)
    else:
        return (0)

score 0 · Answer 1 · answered Oct 10 '18 at 17:48

0

This will solve:

from  math import log
def isPower(A):
    if(A==1):
        return (1)
    if (A&-A)==(A):
        return (1)        
    for i in range(2,int(A**0.5)+1):
        val=log(A,i)
        if(int(val)-val==0):
            return (1)
    else:
        return (0)

If you are looking for reason on why it is not working please refer the below link:

Dealing with accuracy in Python math operations

answered Oct 10 '18 at 17:48

Rahul Agarwal

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thnx, it worked fine except for the case - '2' I added another elif condition to deal with this. – Anantshree Chandola Oct 11 '18 at 05:43
@AnantshreeChandola Also the above code returns 1 for the case '2' when you do isPower(2). – Rahul Agarwal Oct 11 '18 at 09:24

wrong answer for large input

1 Answers1