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.
判断一个数是不是丑数
C++（3ms）：
1 class Solution { 2 public: 3 bool isUgly(int num) { 4 if (num == 0) 5 return false ; 6 while(num%2==0) num/=2 ; 7 while(num%3==0) num/=3 ; 8 while(num%5==0) num/=5 ; 9 return num == 1 ; 10 } 11 };
java(2ms):
1 class Solution { 2 public boolean isUgly(int num) { 3 if (num == 0) 4 return false ; 5 while(num%2==0) num/=2 ; 6 while(num%3==0) num/=3 ; 7 while(num%5==0) num/=5 ; 8 return num == 1 ; 9 } 10 }
原文：http://www.cnblogs.com/mengchunchen/p/7856461.html