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.

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)

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

12 100 200 300 0

5 7 71 73 197 199 281 283

Source: PC Koshien 2007, Preliminary Round
, All-Japan High School Programming Contest, Aizu-Wakamatsu, Japan, 2007

http://www.pref.fukushima.jp/pc-concours/

http://www.pref.fukushima.jp/pc-concours/