{q-,r-,s-,d-,i-}
const maxn=(1 shl 20);zero=ord('0');modu=666013;
{const maxn=(1 shl 10)+6;zero=ord('0');modu=666;}
var t:Text;
   V:Array[0..maxn]of longword;
   A,F:array[0..maxn]of longint;
   Hash:array[0..modu*15]of longint;
   Count,From:array[0..modu]of longint;
   cat,la,lb,lg,unde,i,n,j:longint;s:string;gasit:boolean;
   sol:int64;
   Procedure get(limit:longint);
   begin
      fillchar(f,sizeof(f),0);lg:=0;j:=1;cat:=0;
      for i:=1 to N do
      begin
         while (lg<=limit)and(j<=N)do
         begin if F[A[j]]=0 then inc(lg);inc(f[A[j]]);inc(j);end;
         if lg>limit then inc(sol,j-1) else inc(sol,j);
         dec(f[a[i]]);if F[A[i]]=0 then dec(lg);
      end;
   end;
{var t1:longint;t2:longint absolute $0:$046c;}
begin
{  t1:=t2;                                     }
   assign(T,'secv5.in');reset(T);readln(t,n,la,lb);
   for i:=1 to N do
   begin readln(t,S);for j:=1 to length(S) do V[i]:=V[i]*10+ord(s[j])-zero;end;
   close(T);
{   writeln((T2-t1)/18.2:0:6);  }
   for i:=1 to modu do begin Count[i]:=count[i-1]+15;From[i]:=count[i]+1;end;
   for i:=1 to N do
   begin
      unde:=V[i]-(V[i] div modu)*modu;gasit:=false;
      for j:=From[unde] to Count[unde] do
      if V[Hash[j]]=V[i] then begin gasit:=true;break;end;
      if gasit then A[i]:=A[Hash[j]] else
      begin dec(From[F[i]]);Hash[From[F[i]]]:=i;inc(lg);A[i]:=lg;end;
   end;
   get(lb);sol:=-sol;get(la-1);
   assign(t,'secv5.out');rewrite(T);writeln(T,-sol);close(T);
{   writeln((T2-t1)/18.2:0:6);}
end.