      SUBROUTINE ERLBLO
C
C     This module of the ERLANG program calculates simple
C  blocking from the traffic presented and number of servers.
C
C     B. Z. Lederman     I.T.T. World Communications
C
      BYTE ANS
C
  200 WRITE (5, 205)
  205 FORMAT ( / '$ Enter Erlangs of traffic, Number of trunks: ')
      READ (5, 210, END=260) A, N
  210 FORMAT (F10.2, I4)
C
      BPER = 100. * ERLB(N,A)
C
      WRITE (5, 230) A, N, BPER
  230 FORMAT ('0 Erlangs = ', F7.2, ',  Trunks = ', I4,
     1',  Blocking = ', F6.2, '%' / 1X /
     2'$ Another Blocking Problem [Y/N] ?: ')
      READ (5, 250, END=260) ANS
  250 FORMAT (A1)
      IF ((ANS .EQ. 'Y') .OR. (ANS .EQ. 'y')) GO TO 200
C
  260 RETURN
C
      END