#include<fstream.h>
ifstream fin("date.in");
ofstream fout("date.out");
int f[100];
void main()
{ int i,x;
  while(fin>>x) f[x]++;
  for(i=1;i<=99;i=i+2)
	if(f[i]!=0) fout<<i<<" ";
  fout<<endl;
  for(i=98;i>=0;i=i-2)
	if(f[i]!=0) fout<<i<<" ";
  fout.close();
}