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.public boolean isUgly(int num) {
if (num <= 0) {
return false;
}
while (num != 1) {
if (num % 2 == 0) {
num /= 2;
} else if (num % 3 == 0) {
num /= 3;
} else if (num % 5 == 0) {
num /= 5;
} else {
return false;
}
}
return true;
}
}
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