263. Ugly Number

Write a program to check whether a given number is an ugly number.

Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 6, 8 are ugly while 14 is not ugly since it includes another prime factor 7.

Note that 1 is typically treated as an ugly number.

丑数:0不是丑数!!不提前判断0,容易进入死循环

class Solution(object):
    def isUgly(self, num):
        """
        :type num: int
        :rtype: bool
        """
        if num == 0:
            return False
        while(num%2 == 0):
            num /= 2
        while(num%3 == 0):
            num /= 3
        while(num%5 == 0):
            num /= 5
        if num == 1:
            return True
        else:
            return False

posted @ 2016-02-26 19:33  python挖掘  阅读(172)  评论(0编辑  收藏  举报