BR main
sticks:  .BLOCK 2
take:    .BLOCK 2
;
main:    LDA     21,i
         STA     sticks,d
         LDA     0,i
         STA     take,d
         STRO    msg1,d
         CHARO   '\n',i
         STRO    msg2,d
         CHARO   '\n',i
while:   STRO    msg3,d
         DECO    sticks,d
         STRO    msg4,d
         CHARO   '\n',i
         DECI    take,d
         LDA     take,d
         CPA     1,i
         BRLT    while
         CPA     3,i
         BRGT    while
         LDA     sticks,d
         SUBA    take,d
         STA     sticks,d
         BR      if1
if1:     LDA     sticks,d
         CPA     0,i
         BRLE    win1
         BR      else
else:    LDA     sticks,d
         ANDA    0x0003,i
         STA     take,d
if2:     LDA     take,d
         CPA     0,i
         BREQ    if3
if3:     LDA     1,i
         STA     take,d
         STRO    msg3,d
         DECO    sticks,d
         STRO    msg6,d
         DECO    take,d
         CHARO   '\n',i
         LDA     sticks,d
         SUBA    take,d
         STA     sticks,d
if4:     LDA     sticks,d
         CPA     0,i
         BREQ    win2
         BR      while
win1:    CHARO   '\n',i
         STRO    msg5,d
         BR      stop1
win2:    CHARO   '\n',i
         STRO    msg7,d
stop1:   STOP
msg1:    .ASCII  "There are 21 sticks in a pile.  Each of us will take 1,2 or 3 sticks.\x00"
msg2:    .ASCII  "The player who takes the last stick wins. You can go first.\x00"
msg3:    .ASCII  "There are \x00"
msg4:    .ASCII  " sticks left.  Do you want to take 1,2 or 3?\x00"
msg5:    .ASCII  "You took the last stick.  You won!\x00"
msg6:    .ASCII  " sticks left.  I took \x00"
msg7:    .ASCII  "I took the last stick.  I won!\x00"
         .END