haiku estimating

DIM T(20000) AS INTEGER
h = 9543
U = 1462

N = 10000
DO
  FOR i = 0 TO N: T(i) = 0: NEXT: UM = 0
  FOR i = 1 TO h
    m = INT(RND * N)
    IF T(m) = 0 THEN UM = UM + 1
    T(m) = 1
  NEXT
  PRINT UM; " unique out of "; h; " haikus : N estimate = "; CINT(N)
  IF ABS(UM - U) > 200 THEN a = 100 ELSE a = 10
  IF ABS(UM - U) < 20 THEN a = 1
  IF ABS(UM - U) < 5 THEN a = .1

  IF UM > U THEN N = N - a ELSE N = N + a
  SLEEP
LOOP