import java.util.*;
public class Solution {
/**
*
* @param arr int整型一维数组 the array
* @return int整型
*/
public static int maxLength (int[] arr) {
// write code here
int maxLength = 0;
LinkedList<Integer> list = new LinkedList<>();
for(int i = 0 ; i < arr.length ; i++){
while (list.contains(arr[i])){
list.removeFirst();
}
list.add(arr[i]);
if (list.size() > maxLength){
maxLength = list.size();
}
}
return maxLength;
}
public static void main(String[] args) {
int[] arr = {2,2,3,4,3};
System.out.println(maxLength(arr));
}
}