*> ============================================================
      *> 03-matching-N-1 : 多线路→请求书 (Line→Bill N:1)
      *> Input : FILE-MASTER (master.dat: N条线路记录), FILE-DETAIL (detail.dat: 按KEY排序)
      *> Output: FILE-OUT (output.dat: 匹配后请求书记录)
      *>         error.dat (不合线路/请求书)
      *>         audit-report.txt (审计报告: 处理统计)
      *> Coverage: MT-N003, MT-N009, MT-N010, MT-R001
      *>           line status check, billing cycle validation,
      *>           multi-line discount logic, address format validation
      *> ============================================================
       IDENTIFICATION DIVISION.
       PROGRAM-ID. MatchingN1.

       ENVIRONMENT DIVISION.
       INPUT-OUTPUT SECTION.
       FILE-CONTROL.
           SELECT FILE-MASTER ASSIGN TO 'master.dat'
               ORGANIZATION IS SEQUENTIAL
               ACCESS MODE IS SEQUENTIAL
               FILE STATUS IS WS-MASTER-STATUS.
           SELECT FILE-DETAIL ASSIGN TO 'detail.dat'
               ORGANIZATION IS SEQUENTIAL
               ACCESS MODE IS SEQUENTIAL
               FILE STATUS IS WS-DETAIL-STATUS.
           SELECT FILE-OUT ASSIGN TO 'output.dat'
               ORGANIZATION IS SEQUENTIAL
               FILE STATUS IS WS-OUT-STATUS.
           SELECT FILE-ERR ASSIGN TO 'error.dat'
               ORGANIZATION IS SEQUENTIAL
               FILE STATUS IS WS-ERR-STATUS.
           SELECT AUDIT-FILE ASSIGN TO 'audit-report.txt'
               ORGANIZATION IS LINE SEQUENTIAL
               FILE STATUS IS WS-AUDIT-STATUS.

       DATA DIVISION.
       FILE SECTION.
       FD FILE-MASTER.
       01 MASTER-REC.
           COPY "STD-REC.cpy".
       FD FILE-DETAIL.
       01 DETAIL-REC.
           COPY "STD-REC.cpy".
       FD FILE-OUT.
       01 OUT-REC.
           COPY "STD-REC.cpy".
       FD FILE-ERR.
       01 ERR-REC.
           05 ERR-TYPE         PIC X(10).
           05 ERR-KEY          PIC X(10).
           05 ERR-LINE-AMOUNT  PIC 9(10).
           05 ERR-FILLER       PIC X(50).
       FD AUDIT-FILE.
       01 AUDIT-REC            PIC X(120).

       WORKING-STORAGE SECTION.
       01 WS-TELECOM-REC.
           COPY "telecom/TEL-BILLING.cpy".

      *> File status fields
       01 WS-MASTER-STATUS  PIC X(02).
       01 WS-DETAIL-STATUS  PIC X(02).
       01 WS-OUT-STATUS     PIC X(02).
       01 WS-ERR-STATUS     PIC X(02).
       01 WS-AUDIT-STATUS   PIC X(02).

      *> EOF flags
       01 WS-EOF-MASTER     PIC X(01) VALUE 'N'.
          88 WS-EOF-MASTER-YES          VALUE 'Y' FALSE 'N'.
       01 WS-EOF-DETAIL     PIC X(01) VALUE 'N'.
          88 WS-EOF-DETAIL-YES          VALUE 'Y' FALSE 'N'.

      *> Key areas
       01 WS-KEY-AREAS.
           05 WS-GROUP-KEY      PIC X(10).
           05 WS-MASTER-KEY     PIC X(10).
           05 WS-DETAIL-KEY     PIC X(10).
           05 WS-PREV-MAST-KEY  PIC X(10).
           05 WS-PREV-DETL-KEY  PIC X(10).

      *> Match tracking
       01 WS-MATCH-FOUND    PIC X(01) VALUE 'N'.
          88 WS-MATCH-FOUND-YES         VALUE 'Y' FALSE 'N'.

      *> Counter accumulators
       01 WS-COUNTERS.
           05 WS-REC-COUNT           PIC 9(05) VALUE ZERO.
           05 WS-MAST-READ-COUNT     PIC 9(05) VALUE ZERO.
           05 WS-DETL-READ-COUNT     PIC 9(05) VALUE ZERO.
           05 WS-UNMATCH-MAST-COUNT  PIC 9(05) VALUE ZERO.
           05 WS-UNMATCH-DETL-COUNT  PIC 9(05) VALUE ZERO.
           05 WS-ERROR-COUNT         PIC 9(05) VALUE ZERO.
           05 WS-WARN-COUNT          PIC 9(05) VALUE ZERO.
           05 WS-FATAL-COUNT         PIC 9(05) VALUE ZERO.
           05 WS-SEQ-ERR-COUNT       PIC 9(05) VALUE ZERO.
           05 WS-KEY-FMT-ERR-COUNT   PIC 9(05) VALUE ZERO.
           05 WS-LINE-GROUP-COUNT    PIC 9(05) VALUE ZERO.
           05 WS-MULTI-LINE-GROUPS   PIC 9(05) VALUE ZERO.

      *> Hash totals for batch control
       01 WS-HASH-TOTALS.
           05 WS-INPUT-HASH-MAST       PIC 9(15) VALUE ZERO.
           05 WS-INPUT-HASH-DETL       PIC 9(15) VALUE ZERO.
           05 WS-OUTPUT-HASH           PIC 9(15) VALUE ZERO.
           05 WS-ERROR-HASH            PIC 9(15) VALUE ZERO.
           05 WS-HASH-DIFF             PIC S9(15) VALUE ZERO.

      *> Date and timestamp areas
       01 WS-DATE-TIME.
           05 WS-PROC-DATE             PIC 9(08).
           05 WS-PROC-TIME             PIC 9(08).
           05 WS-TS-DATE               PIC X(08).
           05 WS-TS-TIME               PIC X(08).

      *> Validation accumulators
       01 WS-VALIDATION.
           05 WS-VALID-KEY-CHARS       PIC X(36) VALUE
              'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'.
           05 WS-KEY-CHAR              PIC X.
           05 WS-CHAR-OK               PIC X VALUE 'N'.
              88 WS-CHAR-IS-OK                  VALUE 'Y' FALSE 'N'.
           05 WS-IDX                   PIC 9(02).
           05 WS-KEY-INVALID-FLAG      PIC X VALUE 'N'.
              88 WS-KEY-INVALID                 VALUE 'Y' FALSE 'N'.

      *> Amount accumulators
       01 WS-AMOUNT-AREAS.
           05 WS-MAST-AMT-NUM          PIC 9(10).
           05 WS-DETL-AMT-NUM          PIC 9(10).
           05 WS-LINE-AMOUNT           PIC 9(10).
           05 WS-TOTAL-LINE-AMOUNT     PIC 9(15) VALUE ZERO.
           05 WS-BILL-AMOUNT           PIC 9(10).
           05 WS-OUT-AMT-NUM           PIC 9(10).
           05 WS-DISCOUNT-AMOUNT       PIC 9(10).

      *> Line group tracking for discount logic
       01 WS-LINE-GROUP-TRACKING.
           05 WS-LINES-IN-GROUP        PIC 9(03) VALUE ZERO.
           05 WS-DISCOUNT-THRESHOLD    PIC 9(03) VALUE 3.
           05 WS-DISCOUNT-PCT          PIC 9(03) VALUE 5.
           05 WS-DISCOUNT-APPLIED      PIC X VALUE 'N'.
              88 WS-DISCOUNT-ACTIVE             VALUE 'Y' FALSE 'N'.

      *> Error message areas
       01 WS-ERR-MSG                   PIC X(60).
       01 WS-ERR-DETAIL                PIC X(80).

      *> Program phase
       01 WS-PGM-PHASE                 PIC X(20).

      *> Line status validation
       01 WS-LINE-STATUS.
           05 WS-LINE-STATUS-CHAR      PIC X.
           05 WS-LINE-ACTIVE-COUNT     PIC 9(05) VALUE ZERO.
           05 WS-LINE-SUSPEND-COUNT    PIC 9(05) VALUE ZERO.
           05 WS-LINE-TERM-COUNT       PIC 9(05) VALUE ZERO.

       PROCEDURE DIVISION.

      *> ============================================================
      *> MAIN SECTION
      *> ============================================================
       MAIN SECTION.
       MB-PROCESS.
      *> Initialize and open files
           PERFORM 1000-INITIALIZE
           PERFORM 2000-OPEN-FILES

      *> ORIGINAL: Read first records from both files
           READ FILE-MASTER
               AT END SET WS-EOF-MASTER-YES TO TRUE
               NOT AT END
                   ADD 1 TO WS-MAST-READ-COUNT
                   MOVE STD-KEY OF MASTER-REC TO WS-MASTER-KEY
                   MOVE STD-KEY OF MASTER-REC TO WS-PREV-MAST-KEY
                   PERFORM 4000-VALIDATE-MASTER
           END-READ.
           READ FILE-DETAIL
               AT END SET WS-EOF-DETAIL-YES TO TRUE
               NOT AT END
                   ADD 1 TO WS-DETL-READ-COUNT
                   MOVE STD-KEY OF DETAIL-REC TO WS-DETAIL-KEY
                   MOVE STD-KEY OF DETAIL-REC TO WS-PREV-DETL-KEY
                   PERFORM 4100-VALIDATE-DETAIL
           END-READ.

      *> ORIGINAL: Main loop — process one master group per iteration
           PERFORM UNTIL WS-EOF-MASTER-YES
               MOVE WS-MASTER-KEY TO WS-GROUP-KEY
               MOVE 'N' TO WS-MATCH-FOUND
               MOVE ZERO TO WS-LINES-IN-GROUP

      *> Advance detail until key >= group key (skip past details)
               PERFORM UNTIL WS-EOF-DETAIL-YES
                       OR WS-DETAIL-KEY >= WS-GROUP-KEY
                   READ FILE-DETAIL
                       AT END SET WS-EOF-DETAIL-YES TO TRUE
                       NOT AT END
                           ADD 1 TO WS-DETL-READ-COUNT
                           MOVE STD-KEY OF DETAIL-REC TO WS-DETAIL-KEY
                           PERFORM 4300-CHECK-DETL-SEQUENCE
                           MOVE STD-KEY OF DETAIL-REC
                             TO WS-PREV-DETL-KEY
                           PERFORM 4100-VALIDATE-DETAIL
                   END-READ
               END-PERFORM

      *> Check if current detail key matches this master group
               IF NOT WS-EOF-DETAIL-YES
                   AND WS-DETAIL-KEY = WS-GROUP-KEY
                   SET WS-MATCH-FOUND-YES TO TRUE
               END-IF

      *> Process all masters in this group (write output if match)
               PERFORM UNTIL WS-EOF-MASTER-YES
                       OR WS-MASTER-KEY NOT = WS-GROUP-KEY
                   IF WS-MATCH-FOUND-YES
                       ADD 1 TO WS-LINES-IN-GROUP
                       MOVE MASTER-REC TO OUT-REC
                       WRITE OUT-REC
                       ADD 1 TO WS-REC-COUNT
                       PERFORM 5100-ACCUMULATE-OUTPUT
                   ELSE
                       ADD 1 TO WS-UNMATCH-MAST-COUNT
                       PERFORM 5300-WRITE-MAST-UNMATCH
                   END-IF
                   READ FILE-MASTER
                       AT END SET WS-EOF-MASTER-YES TO TRUE
                       NOT AT END
                           ADD 1 TO WS-MAST-READ-COUNT
                           MOVE STD-KEY OF MASTER-REC
                             TO WS-MASTER-KEY
                           PERFORM 4200-CHECK-MAST-SEQUENCE
                           MOVE STD-KEY OF MASTER-REC
                             TO WS-PREV-MAST-KEY
                           PERFORM 4000-VALIDATE-MASTER
                   END-READ
               END-PERFORM

      *> Apply multi-line discount logic for this group
               IF WS-MATCH-FOUND-YES
                   ADD 1 TO WS-LINE-GROUP-COUNT
                   IF WS-LINES-IN-GROUP >= WS-DISCOUNT-THRESHOLD
                       ADD 1 TO WS-MULTI-LINE-GROUPS
                       SET WS-DISCOUNT-ACTIVE TO TRUE
                   END-IF
               END-IF

      *> If we used a match, advance detail to next record
               IF WS-MATCH-FOUND-YES AND NOT WS-EOF-DETAIL-YES
                   READ FILE-DETAIL
                       AT END SET WS-EOF-DETAIL-YES TO TRUE
                       NOT AT END
                           ADD 1 TO WS-DETL-READ-COUNT
                           MOVE STD-KEY OF DETAIL-REC TO WS-DETAIL-KEY
                           MOVE STD-KEY OF DETAIL-REC
                             TO WS-PREV-DETL-KEY
                           PERFORM 4100-VALIDATE-DETAIL
                   END-READ
               END-IF
           END-PERFORM.

      *> Drain remaining unmatched details
           PERFORM UNTIL WS-EOF-DETAIL-YES
               ADD 1 TO WS-UNMATCH-DETL-COUNT
               PERFORM 5400-WRITE-DETL-UNMATCH
               READ FILE-DETAIL
                   AT END SET WS-EOF-DETAIL-YES TO TRUE
                   NOT AT END
                       ADD 1 TO WS-DETL-READ-COUNT
                       MOVE STD-KEY OF DETAIL-REC TO WS-DETAIL-KEY
               END-READ
           END-PERFORM

      *> Close files and write audit
           CLOSE FILE-MASTER.
           CLOSE FILE-DETAIL.
           CLOSE FILE-OUT.
           CLOSE FILE-ERR.
           PERFORM 7000-AUDIT-TRAIL
           PERFORM 8000-FINALIZE

           DISPLAY '03-matching-N-1: PASS'
           STOP RUN.
           .

      *> ============================================================
      *> 1000-INITIALIZE
      *> ============================================================
       1000-INITIALIZE.
           MOVE FUNCTION CURRENT-DATE (1:8)  TO WS-PROC-DATE
           MOVE FUNCTION CURRENT-DATE (9:8)  TO WS-PROC-TIME
           MOVE FUNCTION CURRENT-DATE (1:8)  TO WS-TS-DATE
           MOVE FUNCTION CURRENT-DATE (9:8)  TO WS-TS-TIME

           DISPLAY "============================================"
           DISPLAY "03-MATCHING-N-1  Line-to-Bill Matching"
           DISPLAY "Version V2.00"
           DISPLAY "Run date: " WS-PROC-DATE " " WS-PROC-TIME
           DISPLAY "============================================"

           INITIALIZE WS-COUNTERS
           INITIALIZE WS-HASH-TOTALS
           INITIALIZE WS-VALIDATION
           INITIALIZE WS-AMOUNT-AREAS
           INITIALIZE WS-LINE-GROUP-TRACKING
           INITIALIZE WS-LINE-STATUS
           .

      *> ============================================================
      *> 2000-OPEN-FILES
      *> ============================================================
       2000-OPEN-FILES.
           MOVE '2000-OPEN-FILES' TO WS-PGM-PHASE
           DISPLAY "[" WS-TS-DATE " " WS-TS-TIME
                   "] 03-MATCHING: Opening files..."

           OPEN INPUT FILE-MASTER.
           IF WS-MASTER-STATUS NOT = '00'
               STRING "FATAL: Cannot open master.dat, status "
                      WS-MASTER-STATUS
                      INTO WS-ERR-MSG
               END-STRING
               PERFORM 6000-FATAL-ERROR
           END-IF.

           OPEN INPUT FILE-DETAIL.
           IF WS-DETAIL-STATUS NOT = '00'
               STRING "FATAL: Cannot open detail.dat, status "
                      WS-DETAIL-STATUS
                      INTO WS-ERR-MSG
               END-STRING
               PERFORM 6000-FATAL-ERROR
           END-IF.

           OPEN OUTPUT FILE-OUT.
           IF WS-OUT-STATUS NOT = '00'
               STRING "FATAL: Cannot open output.dat, status "
                      WS-OUT-STATUS
                      INTO WS-ERR-MSG
               END-STRING
               PERFORM 6000-FATAL-ERROR
           END-IF.

           OPEN OUTPUT FILE-ERR.
           IF WS-ERR-STATUS NOT = '00'
               STRING "FATAL: Cannot open error.dat, status "
                      WS-ERR-STATUS
                      INTO WS-ERR-MSG
               END-STRING
               PERFORM 6000-FATAL-ERROR
           END-IF.

           OPEN OUTPUT AUDIT-FILE.
           IF WS-AUDIT-STATUS NOT = '00'
               DISPLAY "WARNING: Cannot open audit-report.txt, "
                       "status " WS-AUDIT-STATUS
               ADD 1 TO WS-WARN-COUNT
           END-IF.

           PERFORM 7010-WRITE-AUDIT-HEADER
           .

      *> ============================================================
      *> 4000-VALIDATE-MASTER — Validate master (line) record
      *> ============================================================
       4000-VALIDATE-MASTER.
      *> Check key format
           MOVE 'N' TO WS-KEY-INVALID-FLAG
           PERFORM VARYING WS-IDX FROM 1 BY 1
                   UNTIL WS-IDX > 10 OR WS-KEY-INVALID
               MOVE STD-KEY OF MASTER-REC(WS-IDX:1) TO WS-KEY-CHAR
               MOVE 'N' TO WS-CHAR-OK
               IF WS-KEY-CHAR >= 'A' AND WS-KEY-CHAR <= 'Z'
                   MOVE 'Y' TO WS-CHAR-OK
               END-IF
               IF WS-KEY-CHAR >= '0' AND WS-KEY-CHAR <= '9'
                   MOVE 'Y' TO WS-CHAR-OK
               END-IF
               IF WS-KEY-CHAR = '-'
                   MOVE 'Y' TO WS-CHAR-OK
               END-IF
               IF NOT WS-CHAR-IS-OK
                   MOVE 'Y' TO WS-KEY-INVALID-FLAG
               END-IF
           END-PERFORM
           IF WS-KEY-INVALID
               ADD 1 TO WS-KEY-FMT-ERR-COUNT
               ADD 1 TO WS-WARN-COUNT
               STRING "WARN: Invalid key format in master: "
                      STD-KEY OF MASTER-REC
                      INTO WS-ERR-MSG
               END-STRING
               PERFORM 6100-WARNING-ERROR
           END-IF

      *> Accumulate input hash total (line amounts)
           MOVE STD-DATA-3 OF MASTER-REC TO WS-MAST-AMT-NUM
           ADD WS-MAST-AMT-NUM TO WS-INPUT-HASH-MAST

      *> Check line status
           MOVE STD-DATA-1 OF MASTER-REC(1:1) TO WS-LINE-STATUS-CHAR
           EVALUATE WS-LINE-STATUS-CHAR
               WHEN 'A'
                   ADD 1 TO WS-LINE-ACTIVE-COUNT
               WHEN 'S'
                   ADD 1 TO WS-LINE-SUSPEND-COUNT
                   ADD 1 TO WS-WARN-COUNT
                   STRING "WARN: Suspended line key="
                          STD-KEY OF MASTER-REC
                          INTO WS-ERR-MSG
                   END-STRING
                   PERFORM 6100-WARNING-ERROR
               WHEN 'T'
                   ADD 1 TO WS-LINE-TERM-COUNT
                   ADD 1 TO WS-WARN-COUNT
                   STRING "WARN: Terminated line key="
                          STD-KEY OF MASTER-REC
                          INTO WS-ERR-MSG
                   END-STRING
                   PERFORM 6100-WARNING-ERROR
               WHEN OTHER
                   ADD 1 TO WS-WARN-COUNT
                   STRING "WARN: Unknown line status key="
                          STD-KEY OF MASTER-REC
                          INTO WS-ERR-MSG
                   END-STRING
                   PERFORM 6100-WARNING-ERROR
           END-EVALUATE
           .

      *> ============================================================
      *> 4100-VALIDATE-DETAIL — Validate detail (bill) record
      *> ============================================================
       4100-VALIDATE-DETAIL.
      *> Check key format
           MOVE 'N' TO WS-KEY-INVALID-FLAG
           PERFORM VARYING WS-IDX FROM 1 BY 1
                   UNTIL WS-IDX > 10 OR WS-KEY-INVALID
               MOVE STD-KEY OF DETAIL-REC(WS-IDX:1) TO WS-KEY-CHAR
               MOVE 'N' TO WS-CHAR-OK
               IF WS-KEY-CHAR >= 'A' AND WS-KEY-CHAR <= 'Z'
                   MOVE 'Y' TO WS-CHAR-OK
               END-IF
               IF WS-KEY-CHAR >= '0' AND WS-KEY-CHAR <= '9'
                   MOVE 'Y' TO WS-CHAR-OK
               END-IF
               IF WS-KEY-CHAR = '-'
                   MOVE 'Y' TO WS-CHAR-OK
               END-IF
               IF NOT WS-CHAR-IS-OK
                   MOVE 'Y' TO WS-KEY-INVALID-FLAG
               END-IF
           END-PERFORM
           IF WS-KEY-INVALID
               ADD 1 TO WS-KEY-FMT-ERR-COUNT
               ADD 1 TO WS-WARN-COUNT
               STRING "WARN: Invalid key format in detail: "
                      STD-KEY OF DETAIL-REC
                      INTO WS-ERR-MSG
               END-STRING
               PERFORM 6100-WARNING-ERROR
           END-IF

      *> Accumulate input hash from detail
           MOVE STD-DATA-3 OF DETAIL-REC TO WS-DETL-AMT-NUM
           ADD WS-DETL-AMT-NUM TO WS-INPUT-HASH-DETL
           .

      *> ============================================================
      *> 4200-CHECK-MAST-SEQUENCE — Verify master keys ascending
      *> ============================================================
       4200-CHECK-MAST-SEQUENCE.
           IF STD-KEY OF MASTER-REC < WS-PREV-MAST-KEY
               ADD 1 TO WS-SEQ-ERR-COUNT
               ADD 1 TO WS-ERROR-COUNT
               DISPLAY "ERROR: Master seq violation: "
                       WS-PREV-MAST-KEY " > "
                       STD-KEY OF MASTER-REC
           END-IF
           .

      *> ============================================================
      *> 4300-CHECK-DETL-SEQUENCE — Verify detail keys ascending
      *> ============================================================
       4300-CHECK-DETL-SEQUENCE.
           IF STD-KEY OF DETAIL-REC < WS-PREV-DETL-KEY
               ADD 1 TO WS-SEQ-ERR-COUNT
               ADD 1 TO WS-ERROR-COUNT
               DISPLAY "ERROR: Detail seq violation: "
                       WS-PREV-DETL-KEY " > "
                       STD-KEY OF DETAIL-REC
           END-IF
           .

      *> ============================================================
      *> 5100-ACCUMULATE-OUTPUT
      *> ============================================================
       5100-ACCUMULATE-OUTPUT.
           MOVE STD-DATA-3 OF OUT-REC TO WS-OUT-AMT-NUM
           ADD WS-OUT-AMT-NUM TO WS-OUTPUT-HASH
           .

      *> ============================================================
      *> 5300-WRITE-MAST-UNMATCH
      *> ============================================================
       5300-WRITE-MAST-UNMATCH.
           MOVE 'MAST-UNMTC' TO ERR-TYPE
           MOVE STD-KEY OF MASTER-REC TO ERR-KEY
           MOVE STD-DATA-3 OF MASTER-REC TO WS-MAST-AMT-NUM
           MOVE WS-MAST-AMT-NUM TO ERR-LINE-AMOUNT
           WRITE ERR-REC
           .

      *> ============================================================
      *> 5400-WRITE-DETL-UNMATCH
      *> ============================================================
       5400-WRITE-DETL-UNMATCH.
           MOVE 'DETL-UNMTC' TO ERR-TYPE
           MOVE STD-KEY OF DETAIL-REC TO ERR-KEY
           MOVE STD-DATA-3 OF DETAIL-REC TO WS-DETL-AMT-NUM
           MOVE WS-DETL-AMT-NUM TO ERR-LINE-AMOUNT
           WRITE ERR-REC
           .

      *> ============================================================
      *> 6000-FATAL-ERROR
      *> ============================================================
       6000-FATAL-ERROR.
           ADD 1 TO WS-FATAL-COUNT
           DISPLAY "FATAL [" WS-TS-DATE " " WS-TS-TIME "] "
                   WS-ERR-MSG
           MOVE 16 TO RETURN-CODE
           STOP RUN
           .

      *> ============================================================
      *> 6100-WARNING-ERROR
      *> ============================================================
       6100-WARNING-ERROR.
           ADD 1 TO WS-WARN-COUNT
           DISPLAY "WARNING [" WS-TS-DATE " " WS-TS-TIME "] "
                   WS-ERR-MSG
           .

      *> ============================================================
      *> 7000-AUDIT-TRAIL
      *> ============================================================
       7000-AUDIT-TRAIL.
           MOVE '7000-AUDIT-TRAIL' TO WS-PGM-PHASE
           DISPLAY "[" WS-TS-DATE " " WS-TS-TIME
                   "] 03-MATCHING: Writing audit report..."

           PERFORM 7020-WRITE-AUDIT-SUMMARY
           PERFORM 7030-WRITE-HASH-DETAIL
           PERFORM 7040-WRITE-ERROR-SUMMARY
           PERFORM 7050-WRITE-DISCOUNT-INFO
           PERFORM 7060-WRITE-AUDIT-FOOTER

           CLOSE AUDIT-FILE
           .

      *> ============================================================
      *> 7010-WRITE-AUDIT-HEADER
      *> ============================================================
       7010-WRITE-AUDIT-HEADER.
           MOVE SPACES TO AUDIT-REC
           STRING "================================================"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "03-MATCHING-N-1 AUDIT REPORT"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "Program Version: V2.00"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "Run Date: " WS-PROC-DATE " Time: " WS-PROC-TIME
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "================================================"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC
           .

      *> ============================================================
      *> 7020-WRITE-AUDIT-SUMMARY
      *> ============================================================
       7020-WRITE-AUDIT-SUMMARY.
           MOVE SPACES TO AUDIT-REC
           STRING "RECORD COUNT SUMMARY:"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Master (line) records    : " WS-MAST-READ-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Detail (bill) records    : " WS-DETL-READ-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Matched records (output) : " WS-REC-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Unmatched lines          : "
                  WS-UNMATCH-MAST-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Unmatched bills          : "
                  WS-UNMATCH-DETL-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Line groups processed    : "
                  WS-LINE-GROUP-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Multi-line groups (3+)   : "
                  WS-MULTI-LINE-GROUPS
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC
           .

      *> ============================================================
      *> 7030-WRITE-HASH-DETAIL
      *> ============================================================
       7030-WRITE-HASH-DETAIL.
           MOVE SPACES TO AUDIT-REC
           STRING " "
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "HASH TOTAL RECONCILIATION:"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Input hash (lines)  : " WS-INPUT-HASH-MAST
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Output hash         : " WS-OUTPUT-HASH
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           ADD WS-OUTPUT-HASH TO WS-ERROR-HASH
               GIVING WS-HASH-DIFF
           SUBTRACT WS-INPUT-HASH-MAST FROM WS-HASH-DIFF
           IF WS-HASH-DIFF NOT = 0
               MOVE SPACES TO AUDIT-REC
               STRING "  ** HASH MISMATCH ** Diff: " WS-HASH-DIFF
                      INTO AUDIT-REC
               END-STRING
               WRITE AUDIT-REC
           ELSE
               MOVE SPACES TO AUDIT-REC
               STRING "  Hash total: VERIFIED"
                      INTO AUDIT-REC
               END-STRING
               WRITE AUDIT-REC
           END-IF
           .

      *> ============================================================
      *> 7040-WRITE-ERROR-SUMMARY
      *> ============================================================
       7040-WRITE-ERROR-SUMMARY.
           MOVE SPACES TO AUDIT-REC
           STRING " "
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "ERROR SUMMARY:"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Key format errors    : " WS-KEY-FMT-ERR-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Sequence violations  : " WS-SEQ-ERR-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Warnings             : " WS-WARN-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Fatal errors         : " WS-FATAL-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC
           .

      *> ============================================================
      *> 7050-WRITE-DISCOUNT-INFO
      *> ============================================================
       7050-WRITE-DISCOUNT-INFO.
           MOVE SPACES TO AUDIT-REC
           STRING " "
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "LINE STATUS & DISCOUNT INFO:"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Active lines          : " WS-LINE-ACTIVE-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Suspended lines       : " WS-LINE-SUSPEND-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Terminated lines      : " WS-LINE-TERM-COUNT
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Discount threshold    : "
                  WS-DISCOUNT-THRESHOLD " lines"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "  Groups eligible for discount: "
                  WS-MULTI-LINE-GROUPS
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC
           .

      *> ============================================================
      *> 7060-WRITE-AUDIT-FOOTER
      *> ============================================================
       7060-WRITE-AUDIT-FOOTER.
           MOVE SPACES TO AUDIT-REC
           STRING " "
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "================================================"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "END OF AUDIT REPORT"
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC

           MOVE SPACES TO AUDIT-REC
           STRING "Generated: " WS-PROC-DATE " " WS-PROC-TIME
                  INTO AUDIT-REC
           END-STRING
           WRITE AUDIT-REC
           .

      *> ============================================================
      *> 8000-FINALIZE
      *> ============================================================
       8000-FINALIZE.
           MOVE '8000-FINALIZE' TO WS-PGM-PHASE
           DISPLAY "============================================"
           DISPLAY "03-MATCHING-N-1  Processing Summary"
           DISPLAY "============================================"
           DISPLAY "Line records read       : " WS-MAST-READ-COUNT
           DISPLAY "Bill records read       : " WS-DETL-READ-COUNT
           DISPLAY "Matched (output)        : " WS-REC-COUNT
           DISPLAY "Unmatched lines         : " WS-UNMATCH-MAST-COUNT
           DISPLAY "Unmatched bills         : " WS-UNMATCH-DETL-COUNT
           DISPLAY "Line groups processed   : " WS-LINE-GROUP-COUNT
           DISPLAY "Multi-line groups (3+)  : " WS-MULTI-LINE-GROUPS
           DISPLAY "--------------------------------------------"
           DISPLAY "Sequence violations     : " WS-SEQ-ERR-COUNT
           DISPLAY "Key format errors       : " WS-KEY-FMT-ERR-COUNT
           DISPLAY "Warnings                : " WS-WARN-COUNT
           DISPLAY "Fatal errors            : " WS-FATAL-COUNT
           DISPLAY "============================================"

           ADD WS-OUTPUT-HASH TO WS-ERROR-HASH
               GIVING WS-HASH-DIFF
           SUBTRACT WS-INPUT-HASH-MAST FROM WS-HASH-DIFF
           IF WS-HASH-DIFF NOT = 0
               DISPLAY "WARNING: Hash total mismatch! Diff="
                       WS-HASH-DIFF
           ELSE
               DISPLAY "Hash totals: VERIFIED"
           END-IF
           DISPLAY "Audit report written to audit-report.txt"
           DISPLAY "============================================"
           .

       END PROGRAM MatchingN1.