#include<iostream>

 #include<cstdio>

 #include<cstring>

 using namespace std;

 const int maxn = +;

 char s[maxn][];

 int num = ;

 struct Trie

 {

     int son[];

     int ends;

 }t[maxn*];

 void init(int x)

 {

     t[x].ends = ;

     memset(t[x].son,,sizeof(t[x].son));

 }

 void insert(char* s)

 {

     int u = , n = strlen(s);

     for(int i=;i<n;i++)

     {

         int c = s[i]-'a';

         if(!t[u].son[c])

         {

             num++;

             init(num);

             t[u].son[c] = num;

         }

         u = t[u].son[c];

     }

     t[u].ends = ;

 }

 bool query(char* s)

 {

     int u = , n = strlen(s);

     for(int i=;i<n;i++)

     {

         int c = s[i]-'a';

         if(!t[u].son[c])  return false;

         u = t[u].son[c];

     }

     if(t[u].ends == )  return true;

     return false;

 }

 int main()

 {

     //freopen("in.txt","r",stdin);

     int tot = ;

     char s1[],s2[];

     while(~scanf("%s",s[tot++])) insert(s[tot-]);

     for(int i=;i<tot;i++)

     {

         int len = strlen(s[i]);

         for(int j=;j<len;j++)

         {

             memset(s1,,sizeof(s1));

             memset(s2,,sizeof(s2));

             strncpy(s1,s[i],j);

             strncpy(s2,s[i]+j,len-j);

             if(query(s1) && query(s2)) {printf("%s\n",s[i]);break;}

         }

     }

     return ;

 }