struct element string value element next void __fastcall TForm3 BitBtn

struct element
{
  string value;
  element* next;
};
void __fastcall TForm3::BitBtn1Click(TObject *Sender)
{
element *pointer, head;
string s;
char c;
pointer=&head;
FILE *f=fopen(FileListBox1->FileName.c_str(),"r");
while (fgetc(f)!=EOF)
{ c=fgetc(f);
  if (c=='\n')
   {
     pointer->next = new element;
     pointer=pointer->next;
     pointer->value = s;
     pointer->next=NULL;
     s.clear();
   }
  else s+=c;
}
char word[100];
vector <string> v;
string w, str;
pointer=&head;
pointer=pointer->next;
while ( pointer!=NULL)
{
  sscanf(pointer->value.c_str(),"[\w+]", &word);
  w = word;
  if (find(v.begin(),v.end(),w)==v.end())
  v.push_back(w);
  pointer=pointer->next;
}
sort(v.begin(), v.end());
for(int i=0;i<v.size();i++)
 str+=v[i]+",";
ShowMessage(str.c_str());
}