n的幂

Posted 2020-09-19 雪浪snowWave

题目：给你一个数n，判断n是不是某个数的幂，，这个数题目里会给出，leetCode上有三道题，分别是2的幂，3的幂，4的幂

思路：方法都一样，while循环而已

 

//2的幂
public class Solution {
    public boolean isPowerOfFour(int num) {
        if(num>1){
            while(num%2==0)
                num/=2;
        }
        return num==1;
    }
}
//3的幂
public class Solution {
    public boolean isPowerOfFour(int num) {
        if(num>1){
            while(num%3==0)
                num/=3;
        }
        return num==1;
    }
}
//4的幂
public class Solution {
    public boolean isPowerOfFour(int num) {
        if(num>1){
            while(num%4==0)
                num/=4;
        }
        return num==1;
    }
}