package code; /* * 326. Power of Three * 题意:判断该数是否为3的幂 * 难度:Easy * 分类:Math * 思路:除以3,除到不能整除,判断是否为1 * Tips: */ public class lc326 { public boolean isPowerOfThree(int n) { if (n < 1) return false; while (n % 3 == 0) n /= 3; return n == 1; } public boolean isPowerOfThree2(int n) { if(n==1) return true; double d = n; while(d>1){ d=d/3; if(d==1) return true; } return false; } }