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==0)
return false;
if(num==1 || num==2 || num==3 || num==5)
return true;
if(num%2==0)
return isUgly(num/2);
if(num%3==0)
return isUgly(num/3);
if(num%5==0)
return isUgly(num/5);
return false;
}
};
人生有些关口非狠狠的斗一下不可,不能为了混口饭吃而自甘蹉跎。