var n,a,b,nr:longint;
    v:array[1..30000] of integer;
    f:text;
procedure citire;
          var i:integer;
          begin
               assign(f,'teams.in');
               reset(f);
               read(f,n,a,b);
               for i:=1 to n do read(f,v[i]);
               close(f)
          end;
procedure gasire;
          var i,j:longint;
          begin
               nr:=0;
               for i:=1 to n do
                   for j:=i+1 to n do
                       if (v[i]+v[j]>=a) and (v[i]+v[j]<=b) then inc(nr);
          end;
procedure afisare;
          begin
               assign(f,'teams.out');
               rewrite(f);
               write(f,nr);
               close(f)
          end;
begin
     citire;
     gasire;
     afisare
end.