[leetcode]-263. Ugly Number（C语言）

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].

bool isUgly(int num) {
    if(num<1)
        return false;
    while(num>1)
    {
        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 true;
}