# 263. Ugly Number

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`.

**Example 1:**

```
Input: 6
Output: true
Explanation: 6 = 2 × 3
```

**Example 2:**

```
Input: 8
Output: true
Explanation: 8 = 2 × 2 × 2
```

**Example 3:**

```
Input: 14
Output: false 
Explanation: 14 is not ugly since it includes another prime factor 7.
```

**Note:**

1. `1` is typically treated as an ugly number.
2. Input is within the 32-bit signed integer range: \[−231,  231 − 1].

```cpp
bool isUgly(int num) {
    if (num <= 0) return false;
    vector<int> factor = {2, 3, 5};
    for (int f : factor) {
        while (num % f == 0) num /= f;
    }
    return num == 1;
}
```
