1000  COM T$[30],B,B$[42],M,P[6],C[3],D$[9],N,T[7,141]
1001  COM C$[6],O$[6],K,W[6],F,N$[9]
4000  REM
4020  PRINT 
4025  PRINT "  MOD OPTION ";
4030  INPUT O$[1,6]
4035  PRINT 
4040  IF O$[1,3]="ADD" THEN 4140
4045  IF O$[1,3]="DEL" THEN 4250
4050  IF O$[1,3]="HEL" THEN 4100
4055  IF O$[1,3]="PAR" THEN 4410
4060  IF O$[1,3]="RET" THEN 4910
4080  PRINT "INVALID OPTION"
4090  PRINT 
4100  PRINT "ADD:     ACTIVATE A STUDENT"
4105  PRINT "DELETE:  INACTIVATE A STUDENT"
4110  PRINT "HELP:    OBTAIN A LISTING OF OPTIONS"
4115  PRINT "PARAM:   MODIFY THE CLASS PARAMETERS"
4120  PRINT "RETURN:  RETURN TO COMMAND"
4125  PRINT 
4130  GOTO 4020
4135  REM
4140  PRINT "ENTER S.N. TO BE ADDED ";
4145  INPUT I1
4150  PRINT 
4155  LET I=INT(I1-C[1])
4160  IF I>0 AND I<N THEN 4175
4165  PRINT "OUT OF RANGE,  MIN = ";C[1]+1;"MAX = ";C[1]+N-1;
4167  PRINT "I = ";I1
4170  GOTO 4020
4175  IF T[1,I]=-1 THEN 4190
4180  PRINT "STUDENT ALREADY ACTIVE"
4185  GOTO 4020
4190  FOR J=1 TO B
4195  LET T[J,I]=0
4200  NEXT J
4205  LET C[3]=C[3]+1
4210  IF I <= C[2] THEN 4220
4215  LET C[2]=I
4220  PRINT "STUDENT NUMBER";I1;" IS ACTIVATED"
4225  GOTO 4020
4240  REM
4250  PRINT "ENTER S.N. TO BE DELETED ";
4255  INPUT I1
4260  LET I=INT(I1-C[1])
4270  IF I>0 AND I <= C[2] THEN 4285
4275  PRINT "OUT OF RANGE,  MIN = ";C[1]+1;"MAX = ";C[1]+C[2];
4277  PRINT "I = ";I1
4280  GOTO 4020
4285  IF T[1,I]>-1 THEN 4300
4290  PRINT "STUDENT IS NONEXISTANT"
4295  GOTO 4020
4300  FOR J=1 TO B
4305  LET T[J,I]=-1
4310  NEXT J
4315  LET C[3]=C[3]-1
4320  IF I<C[2] THEN 4350
4325  FOR J=C[2] TO 1 STEP -1
4330  IF T[1,J]>-1 THEN 4350
4335  LET C[2]=C[2]-1
4340  NEXT J
4350  PRINT "STUDENT NUMBER ";I1;" IS DELETED"
4355  GOTO 4020
4400  REM
4410  CHAIN "$GPACN"
4900  REM
4910  LET D$=N$
4912  GOSUB 9410
4920  PRINT 
4930  CHAIN "$GPACC"
9400  REM
9405  FILES CLSFIL
9407  REM
9410  READ #1,1
9411  PRINT #1;T$,B,B$,M
9412  MAT  PRINT #1;P,C
9413  PRINT #1;D$,N
9414  FOR Z1=1 TO 6
9415  FOR Z2=1 TO N
9416  PRINT #1;T[Z1,Z2]
9417  NEXT Z2
9418  NEXT Z1
9420  READ #1,1
9421  RETURN 
9999  END 
