LeetCode——Ugly Number

Description：

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.

寻找丑数：

public class Solution {
public boolean isUgly(int num) {

if(num <= 0) {
return false;
}

while(num % 2 == 0) {
num /= 2;
}

while(num % 3 == 0) {
num /= 3;
}

while(num % 5 == 0) {
num /= 5;
}

return num == 1;

}
}