const maxn=1000000;
type sor=array[0..maxn] of byte;
var X,y:sor;
    t:text;
    N,M,W,H:longint;
    I,j,k,xp,yp:longint;
    HANY:longint;

procedure bef(bal,jobb:longint; var W:sor);
          var e:longint;
          begin
           for e:=bal to jobb do w[e]:=1;
          end;

begin
 assign(t,'ograzi.in');
 reset(T);
  read(t,N,M,W,H);
  for i:=0 to maxn do x[i]:=0;
  for i:=0 to maxn do y[i]:=0;

  for i:=1 to n do begin
                    read(t,xp);
                    read(t,yp);
                    bef(xp,xp+w,x);
                    bef(yp,yp+H,y);
                    end;
  hany:=0;
  for i:=1 to m do begin
                   read(t,xp,yp);
                   if y[yp]=1 then
                    if x[xp]=1 then
                     inc(hany);
                   end;


 close(T);
 assign(t,'ograzi.out');
 rewrite(T);
 writeln(t,hany);
 close(T);
end.