Solution.java
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Solution.java
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	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.List;

	public class Solution {
	public static int solution(String n, int b) {
	List<String> cycle = new ArrayList<>();
	List<String> prevCycle = null;

	int k = n.length();

	boolean repeat = false;
	while (!repeat) {
	//obtain sorted x and y
	char[] chars = n.toCharArray();
	Arrays.sort(chars);
	String y = new String(chars); //y is ascending, not x

	StringBuilder sb = new StringBuilder(y);
	String x = sb.reverse().toString();

	//calculate z with base
	int z = Integer.parseInt(x, b) - Integer.parseInt(y, b);
	//obtain n with base
	n = Integer.toString(z, b);

	//prepend zeroes
	int prependCount = k - n.length();
	if (prependCount > 0) {
	char[] prepend = new char[prependCount];
	Arrays.fill(prepend, '0');
	n = new String(prepend) + n;
	}

	//check if we are in a cycle
	int search = cycle.indexOf(n);
	if (search != -1 && search != cycle.lastIndexOf(n)) //if the value is found more than once in the list
	cycle = cycle.subList(search + 1, cycle.size()); //remove irrelevant values before it since we are only interested in the cycle

	cycle.add(n);

	if (prevCycle != null) //if it aint null it would always have a value
	prevCycle.add(prevCycle.remove(0)); //rotate cycle for checking

	if (cycle.equals(prevCycle)) //if what we did is equivalent to rotating the list, we found it
	repeat = true;

	prevCycle = new ArrayList<>(cycle); //reset prevCycle
	}

	return cycle.size() / 2;
	}
	}