Is Power Of Three（是否是3的幂）

From

LeetCode 326

Question

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

C++

class Solution {
public:
    bool isPowerOfThree(int n) {
        
        if(n>1){
            
            while(n%3==0){
               n=n/3;
            }
        }
        
        return n==1;
    }
};

class Solution {
public:
    bool isPowerOfThree(int n) {

      if(n>0){
            return 1162261467%n==0;
      }else{
          return false;
      }
	}
};

Java

public boolean isPowerOfThree(int n) {
    
    if( n > 1 ){
        
        while( n%3 == 0){
            
           n = n/3;
        }
    }
    
    return n == 1;
}