#include <iostream>
#include <bits/stdc++.h>
#include <string>
#include <math.h>

using namespace std;
bool shaml(stack <string> cont , string b);
stack <string> putall(stack <string> cont);
void addrow(vector < vector <char> > *cont,vector < string > c,int row,int col);
void addcol(vector < vector <char> > *cont,vector < string > c,int row,int col);
void ins(vector < vector <char> > *ss,char a,char b);
vector <string> gee(string x);
string getresult(vector < vector <char> > cont);
int getunvistednode(bool arr[],int size);
void die(vector < vector <char> > cont,stack <char> *result,bool arr[],int node);
bool check(char x,vector < vector <char> > cont,bool arr[]);
int getnum(vector < vector <char> > cont,char a);
int main() {



vector < string > c;
string o;


do {
    cin>>o;
    c.push_back(o);

} while(o!="#");
vector < vector <char> > cont;
set <char> q;

for(int i=0;i<c.size()-1;i++){
    for(int j=0;j<(c[i]).length();j++){
        if(!q.count(c[i][j])){
            vector <char >t;
            t.push_back(c[i][j]);
            cont.push_back(t);
            q.insert(c[i][j]);
        }
     //   addrow(&cont,c,i,j);
        addcol(&cont,c,i,j);
    }
}
/*for(int i=0;i<cont.size();i++){
    for(int j=0;j<cont[i].size();j++){
        cout<<cont[i][j]<<"   ";
    }
    cout<<endl;
}*/

//vector < vector <char> > cont;
//cont.resize()

cout<<(getresult(cont));


    }



string getresult(vector < vector <char> > cont){
   int size=cont.size();
   bool death[size]={false};

   stack <char> result;
    int t=getunvistednode(death,size);
    while(getunvistednode(death,size)!=-1){
        die(cont,&result,death,getunvistednode(death,size));
    }
    string x="";
   while(!result.empty()){
    x+=result.top();
    result.pop();
   }
   return  x;
}


void die(vector < vector <char> > cont,stack <char> *result,bool arr[],int node){
    if(arr[node])return;
    arr[node]=true;
    for(int i=1;i<cont[node].size();i++){
      if(!check(cont[node][i],cont,arr)){
        die(cont,&(*result),arr,getnum(cont,cont[node][i]));
      }
    }
    (*result).push(cont[node][0]);
}
int getnum(vector < vector <char> > cont,char a){
   for(int i=0;i<cont.size();i++){
      if(cont[i][0]==a)
        return i;
   }
}
bool check(char x,vector < vector <char> > cont,bool arr[]){
    for(int i=0;i<cont.size();i++){
        if(cont[i][0]==x){
            return arr[i];
        }
    }
}

int getunvistednode(bool arr[],int size){
 for(int i=0;i<size;i++){
    if(!arr[i])
        return i;
 }
 return -1;

}
void addcol(vector < vector <char> > *cont,vector < string > c,int row,int col){
    string guide="";
    for(int i=0;i<col;i++){
        guide+=(c)[row][i];
    }

     for(int i=row+1;i<(c).size()-1;i++){
        string war="";
        if(c[row].length()<col)continue;
        for(int j=0;j<col;j++){
            war+=(c)[i][j];
        }
        if(war==guide){
            ins(&(*cont),c[row][col],c[i][col]);
        }else{
          return;
        }
     }

}
void ins(vector < vector <char> > *ss,char a,char b){
if(a==b)return;
for(int i=0;i<(*ss).size();i++){

    if((*ss)[i][0]==a){
            for(int j=1;j<(*ss)[i].size();j++){
                if((*ss)[i][j]==b){
                    return;
                }
            }
        (*ss)[i].push_back(b);
        return ;
    }
}
}