TITLE    SUDOKU SOLVER
P=17                                   ;Defines AC 17 as the stack pointer.

A=1                                    ;Define two accumulators
B=2                                    ;A and B
CHTTYO==1                              ;Output channel number

PDLLEN==100                            ;Length of push down stack
PDL:    BLOCK PDLLEN                   ;Storage for push down stack

START:  MOVE P,[-PDLLEN,,PDL-1]        ;Initialize the stack
        .CALL [SETZ ? SIXBIT/OPEN/     ;Open the TTY channels
		    [.UAI,,CHTTYO] ? [SIXBIT/TTY/] ((SETZ))]
		 .LOSE %LSFIL


L:      MOVE A, [440700,HELLO]         ;Load the address of the string into A
        PUSHJ P, OUTSTR                ;Print the string.
		JRST L                         ;Keep looping

;Subroutine to output the ASCIZ which starts in the word
;whose address is in A. Clobbers A.
OUTSTR: HRLI A, 440700                ;Make A into a byte pointer to fetch a string
OUTST1: ILDB B, A                     ;Fetch the next character of string into B
        JUMPE B, CPOPJ                ;If it is the terminator, return
	    .IOT CHTTYO,B                 ;Else output the character
		JRST OUTST1                   ;and loop around.

CPOPJ:  POPJ P,                       ;Return

HELLO:  ASCIZ /HELLO WORLD/
        END    START