var
  q: array[1..50000, 1..2] of integer;
  i, j, w, e, a, s, d, n, m, ma, p: integer;
  t: text;

function max: longint;
var
  i, j: integer;
begin
  j := 1;
  for i := 2 to m do
    if q[i, 1] > q[j, 1] then j := i;
  max := j;
end;

begin
  assign(t, 'fisher.in');
  reset(t);
  readln(t, n, m, p);
  for i := 1 to n do
  begin
    readln(t, w, e);
    inc(a, e);
  end;
  for i := 1 to m do
  begin
    readln(t, d, w, e);
    q[i, 1] := e;
    q[i, 2] := w;
  end;
  ma := max;
  while (a > 0) and (q[ma, 1] <> 0) do
  begin
    if a >= q[ma, 2] then begin s := s + q[ma, 2] * q[ma, 1]; a:=a-q[ma, 2]; end else
      begin s := s + a * q[ma, 1];a:=0;end;
    q[ma, 1] := 0;
    ma := max;
  end;
  close(t);
  assign(t, 'fisher.out');
  rewrite(t);
  writeln(t, s);
  close(t);
end.