每天一道LeetCode--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?

public class Solution {
    public boolean isPowerOfThree(int n) {
        int num=n;
        while(num>0&&num%3==0)
            num/=3;
            return num==1;
    }
    //return n > 0 && (1162261467 % n == 0);
}
时间: 2024-10-08 02:33:11

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