Problem:
Twin Prime

Prime numbers are widely applied for cryptographic and communication technology.
A twin prime is a prime number that differs from another prime number by 2.
For example, (5, 7) and (11, 13) are twin prime pairs.

In this problem, we call the greater number of a twin prime "size of the twin prime."

Your task is to create a program which reads an integer n and prints a twin prime which has the maximum size among twin primes less than or equals to n

You may assume that 5 ≤ n ≤ 10000.

Input

The input is a sequence of datasets. The end of the input is indicated by a line containing one zero. Each dataset is formatted as follows:

n (integer)

Output

For each dataset, print the twin prime p and q (p < q). p and q should be separated by a single space.

Sample Input

12
100
200
300
0

Output for the Sample Input

5 7
71 73
197 199
281 283

Solution in JAVA (judge verdict: Wrong Answer)

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		int a = s.nextInt();
		boolean judge = true;
		int count = 0;
		int so[] = new int[a];
		int Max = 0; int Max2 = 0;
		
		for(int num = 2; num < a; num++){
			for(int i = 2; i < num; i++){
				if(num % i == 0){
					judge = false;
					break;
				}
			}
			if(judge){
				//System.out.print(num + " ");
				so[count] = num;
				count++;
			}
			judge = true;
		}
		

		
		for(int i = 1; i< count; i++){
			int check = so[i-1] + 2;
			if(check == so[i]){
				Max = so[i-1];
				Max2 = so[i];
			}
		}
		System.out.println(Max + " " + Max2);
	}
}