[leetcode] 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. 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.

class Solution {
public:
    bool isUgly(int num) {
        if(num==1) return true;
        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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