I have two integer b,n. I need to check if the number n is integer power of number b. For example: 100 is an integer power of 10. As 10^2 = 100. But 110 is not an integer power of 10. How to determine this in coding?
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I have two integer b,n. I need to check if the number n is integer power of number b. For example: 100 is an integer power of 10. As 10^2 = 100. But 110 is not an integer power of 10. How to determine this in coding?
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Try to do like this:
Find log2 of n. Then divide it by log2 of b.
If the result is integer, then n is power of b.
Thank you.
I know a way how to check if a number is an integer or not.
if there is another way, please suggest me.
b divides a if ( (a/b)*b == a)
Its more efficient. Thanks for helping.
Thank you.
But I can't understand the condition for avoiding overflow. Can you please explain why this condition is needed? If I comment out this line, what error will occur.
n = 2*1e18 and b = 1e9
Thanks.
Hello
Check this problem : http://codeforces.net/contest/614/problem/A ,and you will see why this condition is important, and how can overflow occur.
Thanks