263. Ugly Number--LeetCode Record

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.

func isUgly(num: Int) -> Bool {
if num == 0 {
return false
}
var n = num
while(true){
if n % 2 == 0 {
n = n>>1
}else if n % 5 == 0 {
n /= 5
}else if n % 3 == 0 {
n /= 3
}else if n == 1{
return true
}else {
return false
}
}
return false
}