RosettaCodeData/Task/Van-Eck-sequence/COBOL/van-eck-sequence.cob
2026-04-30 12:34:36 -04:00

46 lines
1.2 KiB
COBOL

IDENTIFICATION DIVISION.
PROGRAM-ID. VAN-ECK.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 CALCULATION.
02 ECK PIC 999 OCCURS 1000 TIMES.
02 I PIC 9999.
02 J PIC 9999.
01 OUTPUT-FORMAT.
02 ITEM PIC ZZ9.
02 IDX PIC ZZZ9.
PROCEDURE DIVISION.
B. PERFORM GENERATE-ECK.
PERFORM SHOW VARYING I FROM 1 BY 1 UNTIL I = 11.
PERFORM SHOW VARYING I FROM 991 BY 1 UNTIL I = 1001.
STOP RUN.
SHOW.
MOVE I TO IDX.
MOVE ECK(I) TO ITEM.
DISPLAY 'ECK(' IDX ') = ' ITEM.
GENERATE-ECK SECTION.
B. SET ECK(1) TO 0.
SET I TO 1.
PERFORM GENERATE-TERM
VARYING I FROM 2 BY 1 UNTIL I = 1001.
GENERATE-TERM SECTION.
B. SUBTRACT 2 FROM I GIVING J.
LOOP.
IF J IS LESS THAN 1 GO TO TERM-IS-NEW.
IF ECK(J) = ECK(I - 1) GO TO TERM-IS-OLD.
SUBTRACT 1 FROM J.
GO TO LOOP.
TERM-IS-NEW.
SET ECK(I) TO 0.
GO TO DONE.
TERM-IS-OLD.
COMPUTE ECK(I) = (I - J) - 1.
DONE. EXIT.