Towers of Hanoi Puzzle (iterative) for NPS MICRO-COBOL
This program solves the Towers of Hanoi puzzle with five disks. It is an adaptation of Er's LLHanoi Hanoi Tower loop less algorithm for NPS MICRO-COBOL.
NPS MICRO-COBOL has a lot of limitations:
- Tables can have only one dimension.
- Optional keywords are not implemented. E.g.
GOis allowed, but notGO TO. PERFORM ... VARYINGis implemented, but doesn't always work.- The
GIVINGword is not implemented. - The relational characters '<', '=' and '>' are not implemented. You must use the textual equivalents.
IFstatements must end withEND-IF.- Strings are to be enclosed in apostrophes. Quotes are not allowed.
Compilation
A>COBOL HANOI2 $S
The source code follows the conventional fixed format with the first six characters reserved for sequence number, and therefore the compilation command must be given the '$S' flag.
IDENTIFICATION DIVISION.
PROGRAM-ID. ITERATIVE-TOWERS-OF-HANOI.
AUTHOR. SOREN ROUG.
DATE-WRITTEN. 2019-08-07.
* Er's LLHanoi Hanoi Tower loop less algorithm
* http://hanoitower.mkolar.org/algo.html
ENVIRONMENT DIVISION.
CONFIGURATION SECTION.
SOURCE-COMPUTER. LINUX.
OBJECT-COMPUTER. KAYPRO4.
DATA DIVISION.
WORKING-STORAGE SECTION.
77 NUM-DISKS PIC 99 VALUE 5.
77 N1 PIC 99 USAGE COMP.
77 TO-PEG PIC 99 USAGE COMP.
77 MOD3 PIC 99 USAGE COMP.
77 I PIC 99 USAGE COMP.
77 IMASK1 PIC 99 USAGE COMP.
77 DIR PIC 99 USAGE COMP.
01 STACKNUMS.
10 D OCCURS 20 PIC 99 USAGE COMP.
01 GAMESET.
10 S OCCURS 20 PIC 99 USAGE COMP.
PROCEDURE DIVISION.
HANOI.
DISPLAY 'TOWERS OF HANOI PUZZLE WITH ' NUM-DISKS ' DISKS.'.
MOVE NUM-DISKS TO N1.
ADD 1 TO N1.
MOVE 1 TO I.
PERFORM INIT-PUZZLE UNTIL I GREATER N1.
MOVE NUM-DISKS TO DIR.
MOVE NUM-DISKS TO I.
DIVIDE 2 INTO I.
MULTIPLY 2 BY I.
SUBTRACT I FROM DIR.
PERFORM MOVE-DISK THRU MOVE-END UNTIL I EQUAL N1.
DISPLAY 'TOWERS OF HANOI PUZZLE COMPLETED!'.
STOP RUN.
INIT-PUZZLE.
MOVE 1 TO D (I).
MOVE I TO S (I).
ADD 1 TO I.
MOVE-DISK.
MOVE S (1) TO I.
IF I EQUAL N1
GO MOVE-END
END-IF.
MOVE I TO IMASK1.
DIVIDE 2 INTO IMASK1.
MULTIPLY 2 BY IMASK1.
MOVE D (I) TO TO-PEG.
IF I NOT EQUAL IMASK1
ADD DIR TO TO-PEG
ELSE
ADD 1 TO TO-PEG
SUBTRACT DIR FROM TO-PEG
END-IF.
MOVE TO-PEG TO MOD3.
DIVIDE 3 INTO MOD3.
MULTIPLY 3 BY MOD3.
SUBTRACT MOD3 FROM TO-PEG.
ADD 1 TO TO-PEG.
DISPLAY 'MOVE DISC ' I ' FROM ' D (I) ' TO ' TO-PEG.
MOVE TO-PEG TO D (I).
MOVE 1 TO S (1).
MOVE I TO TO-PEG.
ADD 1 TO TO-PEG.
MOVE S (TO-PEG) TO S (I).
MOVE I TO S (TO-PEG).
ADD 1 TO S (TO-PEG).
MOVE-END.
EXIT.
Output
A>exec hanoi2 NPS MICRO-COBOL LOADER VERSION 2.1 HANOI2 LOADED NPS MICRO-COBOL INTERPRETER VERSION 2.1 EXECUTION BEGINS TOWERS OF HANOI PUZZLE WITH 05 DISKS. MOVE DISC 01 FROM 01 TO 03 MOVE DISC 02 FROM 01 TO 02 MOVE DISC 01 FROM 03 TO 02 MOVE DISC 03 FROM 01 TO 03 MOVE DISC 01 FROM 02 TO 01 MOVE DISC 02 FROM 02 TO 03 MOVE DISC 01 FROM 01 TO 03 MOVE DISC 04 FROM 01 TO 02 MOVE DISC 01 FROM 03 TO 02 MOVE DISC 02 FROM 03 TO 01 MOVE DISC 01 FROM 02 TO 01 MOVE DISC 03 FROM 03 TO 02 MOVE DISC 01 FROM 01 TO 03 MOVE DISC 02 FROM 01 TO 02 MOVE DISC 01 FROM 03 TO 02 MOVE DISC 05 FROM 01 TO 03 MOVE DISC 01 FROM 02 TO 01 MOVE DISC 02 FROM 02 TO 03 MOVE DISC 01 FROM 01 TO 03 MOVE DISC 03 FROM 02 TO 01 MOVE DISC 01 FROM 03 TO 02 MOVE DISC 02 FROM 03 TO 01 MOVE DISC 01 FROM 02 TO 01 MOVE DISC 04 FROM 02 TO 03 MOVE DISC 01 FROM 01 TO 03 MOVE DISC 02 FROM 01 TO 02 MOVE DISC 01 FROM 03 TO 02 MOVE DISC 03 FROM 01 TO 03 MOVE DISC 01 FROM 02 TO 01 MOVE DISC 02 FROM 02 TO 03 MOVE DISC 01 FROM 01 TO 03 TOWERS OF HANOI PUZZLE COMPLETED! 0 EXECUTION ERRORS