Find the missing permutation: Difference between revisions

=={{header|8080 Assembly}}==

<lang asm>PRMLEN: equ 4 ; length of permutation string

puts: equ 9 ; CP/M print string

org 100h

lxi d,perms ; Start with first permutation

perm: lxi h,mperm ; Missing permutation

mvi b,PRMLEN ; Length of permutation

char: ldax d ; Load character

ora a ; Done?

jz done

xra m ; If not, XOR into missing permutation

mov m,a

inx h ; Increment pointers

inx d

dcr b ; Next character of current permutation

jnz char

jmp perm ; Next permutation

done: lxi d,msg ; Print the message and exit

mvi c,puts

jmp 5

msg: db 'Missing permutation: '

mperm: db 0,0,0,0,'$' ; placeholder

perms: db 'ABCD','CABD','ACDB','DACB','BCDA','ACBD','ADCB','CDAB'

db 'DABC','BCAD','CADB','CDBA','CBAD','ABDC','ADBC','BDCA'

db 'DCBA','BACD','BADC','BDAC','CBDA','DBCA','DCAB'

db 0 ; end marker </lang>

{{out}}

<pre>Missing permutation: DBAC</pre>