326. Power of Three

Given an integer, write a function to determine if it is a power of three.

Follow up:
Could you do it without using any loop / recursion?

Solution:

Loop/ recursion should be straightforward.

The trick solution is to not use them.

Like we did in power of 2, since 3 is a prime number, any integer that is power of three should be a divisor of the biggest power of three in integer range. And any other integers are not be able to divided by that number.

 public boolean isPowerOfThree(int n) {  
     return (n>0 && 1162261467%n==0);  
   }