75

#include<iostream>
#include<cstring>
#include<fstream>
using namespace std;
ifstream fin1("x.txt.cpp");
char s[4][20];
int main()
   {
     int i,j;
     for(i=1;i<=4;i++)  cin>>s[i];

     for(i=1;i<=4;i++)
      {
       for(j=i+1;j<=4;j++)
       {
         if(strstr(s[i],s[j])!=0)
         {
            cout<<s[i]<<" "<<s[j];
            cout<<endl;

         }
         if(strstr(s[j],s[i])!=0)
         {
           cout<<s[j]<<" "<<s[i];
           cout<<endl;

         }
      }
      }
   }