丑数 https://leetcode-cn.com/problems/ugly-number/ 判断一个数不是丑数难,但是判断一个数是否是丑数简单。 1 2 3 4 5 6 7 for i = 2,3,5 while(num % i == 0) num = num/i if(num == 1) return true; else return false; `` 丑数Ⅱ https://leetcode-cn.com/problems/ugly-number-ii/ 三指针法 超级丑数 https://leetcode-cn.com/problems/super-ugly-number/