263. Ugly Number

Topic:

Write a program to check whether a given number was an ugly number.

Ugly numbers is positive numbers whose prime factors only include 2, 3, 5 . For example, was ugly while was not 6, 8 14 ugly since it includes another prime factor 7 .

Note that's 1 typically treated as an ugly number.

Answer:

The base factor contains only 2 or 3 or 5 positive numbers called the ugly number, 1 is a special ugly number. The idea is to re-judge these three-number loops.

1 classSolution {2  Public:3     BOOLisugly (intnum) {4         if(num<=0){5             return false;6         }7         if(num==1){8             return true;9         }Ten          while(num%2==0){ Onenum=num/2; A         } -          while(num%3==0){ -num=num/3; the         } -          while(num%5==0){ -num=num/5; -         } +         if(num==1){ -             return true; +         } A         Else{ at             return false; -         } -     } -};

263. Ugly Number