max% = 0
      nlicence% = 0
      file% = OPENIN("mlijobs.txt")

      WHILE NOT EOF#file%
        a$ = GET$#file%
        stamp$ = MID$(a$, 15, 19)
        IF INSTR(a$, "OUT") THEN
          nlicence% += 1
          IF nlicence% > max% THEN
            max% = nlicence%
            start$ = stamp$
          ENDIF
        ENDIF
        IF INSTR(a$, "IN") THEN
          IF nlicence% = max% THEN
            finish$ = previous$
          ENDIF
          nlicence% -= 1
        ENDIF
        previous$ = stamp$
      ENDWHILE
      CLOSE #file%

      PRINT "Maximum licences checked out = " ; max%
      PRINT "From " start$ " to " finish$
      END