-
Notifications
You must be signed in to change notification settings - Fork 9
/
PersistentBugger.java
46 lines (39 loc) · 1.14 KB
/
PersistentBugger.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
package main.java.kyu6;
/**
* 6 kyu - Persistent Bugger
*
* https://www.codewars.com/kata/55bf01e5a717a0d57e0000ec
*
* Details:
*
* Write a function, persistence, that takes in a positive parameter num and returns its
* multiplicative persistence, which is the number of times you must multiply the digits in num
* until you reach a single digit.
*/
import org.junit.Assert;
import org.junit.Test;
public class PersistentBugger {
public static int persistence(final long n) {
return persistenceCount(n, 0);
}
public static int persistenceCount(long n, int currentCount) {
long l = n;
if (l < 10) {
return currentCount;
}
long nextN = 1;
while (l != 0) {
nextN *= l % 10;
l /= 10;
}
return persistenceCount(nextN, ++currentCount);
}
@Test
public void basicTests() {
System.out.println("****** Basic Tests ******");
Assert.assertEquals(3, persistence(39));
Assert.assertEquals(0, persistence(4));
Assert.assertEquals(2, persistence(25));
Assert.assertEquals(4, persistence(999));
}
}