UVA Problem ID 10038 (Jolly Jumpers)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main
{
	public static void main(String[] args) throws IOException
	{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String input;
		StringBuffer sb = new StringBuffer("");
		while((input=br.readLine())!=null)
		{
			String s[]=input.split(" ");
			int n=Integer.parseInt(s[0]);
			if(n>3000)
				break;
			int sequence[]=new int[n];
			boolean flag[]=new boolean[n-1];
			for (int i = 0; i < sequence.length; i++)
			{
				sequence[i]=Integer.parseInt(s[i+1]);
			}
			for (int i = 0; i < sequence.length-1; i++)
			{
				int diff=Math.abs(sequence[i]-sequence[i+1]);
				//System.out.println("diff ="+diff);
				if(diff >=1 && diff<=n-1)
				{
					flag[diff-1]=true;
				}
			}
			boolean isjolly=true;
			for (int i = 0; i < flag.length; i++)
			{
				if(!flag[i])
				{
					isjolly=false;
					break;
				}
			}
			if(isjolly)
				sb.append("Jolly\n");
			else
				sb.append("Not jolly\n");
		}
		System.out.print(sb);
	}
}