Очередь в динамической памяти

#include <vcl.h>
#pragma hdrstop
 
#include "Sp.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
char x[20];
struct spis
{
char inf[20];
spis *next;
spis *pred;
} ;
spis  *T=NULL,*N=NULL;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
void vvod(char x[],TEdit*Edit1)
{
strcpy (x, Edit1->Text.c_str() );
}
//---------------------------------------------------------------------------
spis *add(spis *T, char x[])
{
spis *M=new spis;
strcpy(M->inf,x);
M->next=NULL;
M->pred=NULL;
if (T!=NULL)
 {
  T->pred=M;
  M->next=T;
 }
T=M;
return T;
}
//---------------------------------------------------------------------------
spis *del(spis *T,spis *N, char x[])
{ 
if (T==NULL)
ShowMessage("очередь пуста");
else
 
 
}
//---------------------------------------------------------------------------
void watch(spis *T,TMemo*Memo1)
{
spis *i=T;
while (i!=NULL)
{
Memo1->Lines->Add((AnsiString)i->inf);
i=i->next;
}
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
if (RadioButton1->Checked==true)
{vvod(x,Edit1);
T=add (T,x);
Edit1->SetFocus();
}
if (RadioButton2->Checked==true)
{
T=del (T,N,x);
 Edit1->Text=(AnsiString)x;
}
 if (RadioButton3->Checked==true)
{
Memo1->Clear();
watch (T,Memo1);
}
}