IDENTIFICATION DIVISION.
        PROGRAM-ID.INDEX-FILE.

       ENVIRONMENT DIVISION.
        INPUT-OUTPUT SECTION.
           FILE-CONTROL.
               SELECT INDX-FILE ASSIGN TO DISK
                ORGANIZATION IS INDEXED
                ACCESS MODE IS DYNAMIC
                RECORD KEY IS FRNO.

       DATA DIVISION.
        FILE SECTION.
          FD INDX-FILE 
             VALUE OF FILE-ID IS "INDEX.TXT".

               01 INDX-REC.
                  05 FRNO   PIC 99.
                  05 FNAME  PIC X(10).
                  05 FMARKS PIC 999.


        WORKING-STORAGE SECTION.
               01 OPERATION PIC 9.
                  88 INS VALUE 1.
                  88 DEL VALUE 2.
                  88 UPD VALUE 3.
                  88 VIEW VALUE 4.
                  88 PRINTALL VALUE 5.
                  88 EXIT1 VALUE 0.

               01 CH1 PIC X VALUE "Y". 
               01 FIELD PIC X(6) VALUE ALL SPACE.
               01 EOF PIC X VALUE "Y".
               
       PROCEDURE DIVISION.
        PARA-1.
           
           OPEN I-O INDX-FILE.

           PERFORM UNTIL CH1="N"
               DISPLAY "WHICH OPERATION DO YOU WANT TO PERFORM"
               DISPLAY "1-INSERT"
               DISPLAY "2-DELETE"
               DISPLAY "3-UPDATE"
               DISPLAY "4-VIEW"
               DISPLAY "0-EXIT"
               DISPLAY "ENTER NUMBER TO PERFORM OPERATION: "
               ACCEPT OPERATION

               EVALUATE TRUE 
                    WHEN INS PERFORM INS-PARA
                    WHEN DEL PERFORM DEL-PARA
                    WHEN UPD PERFORM UPD-PARA
                    WHEN VIEW PERFORM VIEW-PARA
                    WHEN EXIT1 PERFORM EXIT-PARA
               END-EVALUATE

           END-PERFORM.

           CLOSE INDX-FILE.

           STOP RUN.

        INS-PARA.
      *     DISPLAY "INS-PARA".
            DISPLAY "ENTER STUDENT NUMBER : ".
            ACCEPT FRNO.

            DISPLAY "ENTER STUDENT NAME : ".
            ACCEPT FNAME.

            DISPLAY "ENTER STUDENT MARKS : ".
            ACCEPT FMARKS.

            WRITE INDX-REC
               INVALID KEY DISPLAY "RECORD ALREADY EXIST WITH ROLL NUMB
      - "ER"
            END-WRITE.

        DEL-PARA.
      *         DISPLAY "DEL-PARA".
            DISPLAY "WHICH RECORD YOU WANT TO DELETE : ".
            ACCEPT FRNO.

            DELETE INDX-FILE
               INVALID KEY DISPLAY "RECORD DOES NOT EXIST"
               NOT INVALID KEY
                    DISPLAY "RECORD HAS BEEN DELETED"
            END-DELETE.

        UPD-PARA.
      *         DISPLAY "UPD-PARA".
                
            DISPLAY "WHICH RECORD YOU WANT TO UPDATE : ".
            DISPLAY "ENTER ROLL NUMBER TO UPDATE : ".
            ACCEPT FRNO.

            READ INDX-FILE
               INVALID KEY DISPLAY "RECORD DOES NOT EXIST" 
               NOT INVALID KEY 
                    DISPLAY "WHICH FIELD YOU WANT TO UPDATE"
                    DISPLAY "1-NAME OR 2-MARKS"
                    ACCEPT FIELD

                    IF FIELD=1
                         DISPLAY "ENTER VALUE FOR NAME : "
                         ACCEPT FNAME
                    ELSE
                    IF FIELD=2
                         DISPLAY "ENTER VALUE FOR MARKS : "
                         ACCEPT FMARKS
                    END-IF
                    END-IF

                    REWRITE INDX-REC
                    DISPLAY "RECORD HAS BEEN UPDATED"
            END-READ.
            
        VIEW-PARA.
      *         DISPLAY "VIEW-PARA".
            DISPLAY "WHICH RECORD YOU WANT TO VIEW".
            ACCEPT FRNO.

            READ INDX-FILE
               INVALID KEY DISPLAY "RECORD DOES NOT EXIST"
               NOT INVALID KEY
                    DISPLAY "ROLL NO->" FRNO
                    DISPLAY "NAME   ->" FNAME
                    DISPLAY "MARKS  ->" FMARKS
            END-READ.
        
        EXIT-PARA.
            MOVE "N" TO CH1.


******************************* OUTPUT ************************************
WHICH OPERATION DO YOU WANT TO PERFORM:
1-INSERT
2-DELETE
3-UPDATE
4-VIEW
0-EXIT
ENTER NUMBER TO PERFORM OPERATION:
1
ENTER STUDENT ROLL NO.:
1
ENTER STUDENT NAME:
MANALI
ENTER STUDENT MARKS:
35

WHICH OPERATION DO YOU WANT TO PERFORM:
1-INSERT
2-DELETE
3-UPDATE
4-VIEW
0-EXIT
ENTER NUMBER TO PERFORM OPERATION:
2
ENTER STUDENT ROLL NO.:
2
RECORD HAS BEEN DELETED

WHICH OPERATION DO YOU WANT TO PERFORM:
1-INSERT
2-DELETE
3-UPDATE
4-VIEW
0-EXIT
ENTER NUMBER TO PERFORM OPERATION:
3
ENTER STUDENT ROLL NO.:
1
WHICH FIELD YOU WANT TO UPDATE:
1-NAME OR 2-MARKS
2
ENTER NEW VALUE FOR MARKS:
37
RECORD HAS BEEN UPDATED

WHICH OPERATION DO YOU WANT TO PERFORM:
1-INSERT
2-DELETE
3-UPDATE
4-VIEW
0-EXIT
ENTER NUMBER TO PERFORM OPERATION:
4
WHICH RECORD YOU WANT TO VIEW
1
ROLL NO->1
NAME->MANALI
MARKS->37