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.
public class Solution { public boolean isUgly(int num) { if(num < 0 ){ return false; } while(num >= 2){ if(num%2 == 0){ num = num/2; } else if(num%3 == 0){ num = num/3; } else if(num%5 == 0){ num = num/5; } else{ return false; } } return num == 1; } }
原文：http://www.cnblogs.com/incrediblechangshuo/p/5665068.html