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.

思路

此题甚易，我们只需要注意题意中”only include”一词即可。

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