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:
class Solution {
private:
public:
bool isUgly(int num) {
if(!num) {
return false;
}
while(!(num % 2)) {
num /= 2;
}
while(!(num % 3)) {
num /= 3;
}
while(!(num % 5)) {
num /= 5;
}
return num == 1;
}
};