import java.util.HashSet;
import java.util.Set;
public class MyClass {
private static int countMaxConsecutiveSetOfNumbers(int[] arr) {
int size = arr.length;
HashSet<Integer> set = new HashSet<Integer>();
for (int i = 0; i < size; i++)
set.add(arr[i]);
int mx = 0;
for (int i = 0; i < size; i++) {
if (set.contains(arr[i])) {
int temp = arr[i];
while (set.contains(temp))
temp++;
mx = Math.max(mx, temp - arr[i]);
}
}
return mx;
}
public static void main(String args[]) {
int[] arr = {22, 3, 21, 32, 24, 31, 4, 99, 23};
// 21 22 23 24
System.out.print(countMaxConsecutiveSetOfNumbers(arr));
}
}
/*
run:
4
*/