[LintCode] Ugly Number 丑陋数

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## [LintCode] Ugly Number 丑陋数

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.

Notice

Note that 1 is typically treated as an ugly number.

Example
Given num = 8 return true
Given num = 14 return false

LeetCode上的原题，请参见我之前的博客Ugly Number

```class Solution {
public:
/**
* @param num an integer
* @return true if num is an ugly number or false
*/
bool isUgly(int num) {
while (num > 1) {
if (num % 2 == 0) num /= 2;
else if (num % 3 == 0) num /= 3;
else if (num % 5 == 0) num /= 5;
else return false;
}
return num == 1;
}
};```

```class Solution {
public:
/**
* @param num an integer
* @return true if num is an ugly number or false
*/
bool 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;
}
};```

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