Description#
An ugly number is a positive integer whose prime factors are limited to 2, 3, and 5.
Given an integer n, return true if n is an ugly number.
Example 1:
Input: n = 6
Output: true
Explanation: 6 = 2 × 3
Example 2:
Input: n = 1
Output: true
Explanation: 1 has no prime factors, therefore all of its prime factors are limited to 2, 3, and 5.
Example 3:
Input: n = 14
Output: false
Explanation: 14 is not ugly since it includes the prime factor 7.
Constraints:
Solutions#
Solution 1#
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| class Solution:
def isUgly(self, n: int) -> bool:
if n < 1:
return False
for x in [2, 3, 5]:
while n % x == 0:
n //= x
return n == 1
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| class Solution {
public boolean isUgly(int n) {
if (n < 1) return false;
while (n % 2 == 0) {
n /= 2;
}
while (n % 3 == 0) {
n /= 3;
}
while (n % 5 == 0) {
n /= 5;
}
return n == 1;
}
}
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| class Solution {
public:
bool isUgly(int n) {
if (n < 1) return false;
while (n % 2 == 0) {
n /= 2;
}
while (n % 3 == 0) {
n /= 3;
}
while (n % 5 == 0) {
n /= 5;
}
return n == 1;
}
};
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| func isUgly(n int) bool {
if n < 1 {
return false
}
for _, x := range []int{2, 3, 5} {
for n%x == 0 {
n /= x
}
}
return n == 1
}
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| /**
* @param {number} n
* @return {boolean}
*/
var isUgly = function (n) {
if (n < 1) return false;
while (n % 2 === 0) {
n /= 2;
}
while (n % 3 === 0) {
n /= 3;
}
while (n % 5 === 0) {
n /= 5;
}
return n === 1;
};
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| class Solution {
/**
* @param Integer $n
* @return Boolean
*/
function isUgly($n) {
while ($n) {
if ($n % 2 == 0) {
$n = $n / 2;
} elseif ($n % 3 == 0) {
$n = $n / 3;
} elseif ($n % 5 == 0) {
$n = $n / 5;
} else {
break;
}
}
return $n == 1;
}
}
|
