import std.stdio;
import std.conv;
import std.string;
import std.typecons;
import std.algorithm;
import std.array;
import std.range;
import std.math;
import std.container;
import std.datetime;

void main()
{
  immutable MAX = 10001;

  bool p[MAX];
  p[] = 1;
  p[0..2] = 0;
  foreach (i; 2..sqrt(MAX*1.0).ceil.to!int) {
    if (p[i]) {
      foreach (j; iota(i*2, MAX, i))
        p[j] = 0;
    }
  }

  while (1) {
    auto n = readln.chomp.to!int;
    if (!n) break;
    while (1) {
      if (p[n] && p[n-2]) {
        writeln(n-2, " ", n);
        break;
      }
      n--;
    }
  }
}