The Museum of HP Calculators

Mastermind for the HP-41

This program is supplied without representation or warranty of any kind. Jean-Marc Baillard and The Museum of HP Calculators therefore assume no responsibility and shall have no liability, consequential or otherwise, of any kind arising from the use of this program material or any part thereof.

Overview

1°) Program#1 ( 6-digit numbers only )
2°) A Micro-Code Routine
3°) Program#2 ( from 1- to 10-digit numbers )

-A number is chosen by the HP-41 and you have to find it by several guesses
-The calculator tells you how many digits of your guess are in a right position and how many are in a wrong position
-The digits range from 1 to 9
-0 is not allowed in the following versions

1°) Program#1 ( 6-digit numbers )

Data Registers: • R00 = pseudo-random numbers ( This register is to be initialized before executing "MMD" )

R01 thru R06 = +/- the digits of the hidden number R10 = number of your guesses
R07 to R09 = counters R11 thru R16 = the digits of your guess or 0
Flag: F29
Subroutines: /

01 LBL "MMD"
02 6
03 STO 10
04 LBL 00                         Lines 02 thru 16 computes the 6 digits of the mystery number
05 SIGN
06 RCL 00
07 R-D
08 FRC
09 STO 00
10 9                                   If, for instance, you want to use digits from 1 to 7 only, replace this line by 7
11 *
12 +
13 INT
14 STO IND 10
15 DSE 10
16 GTO 00
17 X<>Y
18 FIX 0
19 CF 29
20 LBL 01
21 " WAIT . . ."
22 AVIEW
23 CLA
24 ARCL X
25 16.01
26 STO 07
27 STO 08
28 6
29 STO 09
30 RCL Z
31 ISG 10
32 LBL 02
33 ENTER^
34 INT
35 10
36 ST/ Z
37 MOD
38 STO IND 07
39 RCL IND Z
40 ABS
41 X#Y?
42 GTO 02
43 "~*"                        append *
44 ST- IND 07
45 CHS
46 LBL 02
47 STO IND T
48 R^
49 DSE X
50 R^
51 DSE 07
52 GTO 02
53 ALENG                 if you don't have an X-functions module, replace lines 53-54 by RCL 17   6
54 12                                                                                       add   ISG 17 after line 45
55 X=Y?                                                                          and add   0 STO 17 RDN after line 20
56 GTO 05
57 LBL 03
58 RCL 08
59 STO 07
60 LBL 04
61 RCL IND 07
62 RCL IND 09
63 X#Y?
64 GTO 04
65 "~/"                        append /
66 ST- IND 07
67 CHS
68 STO IND 09
69 LBL 04
70 DSE 07
71 GTO 04
72 DSE 09
73 GTO 03
74 PROMPT
75 GTO 01
76 LBL 05
77 RCL 10
78 FIX 4
79 SF 29
80 AVIEW
81 END

( 138 bytes / SIZE 017 )

Example: 1 STO 00

   111111   XEQ "MMD" >>>> " WAIT. . ."     "111111*"               there is one "1"
   122222           R/S                    " WAIT. . ."      "122222*"               the "1" is in right position and there is no "2"
   133333           R/S                    " WAIT. . ."      "133333***"           the "1" & two "3"s are in right position
   133444           R/S                    " WAIT. . ."      "133444*/ /"            the "1" is in right position but the two "3"s are in a wrong location. There is no "4"
   155335"          R/S                    " WAIT. . ."      "155335**/"            ------ and one "3" are well placed. There is no "5"
   166363           R/S                    " WAIT. . ."      "166363****"         the "1" and the two "3"s are well placed and there is one "6"
   167373           R/S                    " WAIT. . ."      "167373***/"          -------------------------------------- the "6" is in a wrong location and there is no "7"
   186383           R/S                    " WAIT. . ."      "186383****"         the "1" "6" "3" "3" are in right position. There is no "8"
   196393           R/S                    " WAIT. . ."      "196393******"     the hidden number was 196393

-Press the backarrow-key to see that you've made 9 guesses ( this number is also in register R10 )

Notes:

-Each "*" represents a well placed digit, each "/" denotes a digit in a wrong position
-Other characters are of course possible.
-The above strategy is not the best one!
-You have to " WAIT. . ." for 14 seconds ( approximately )
-The hidden number is computed after your first guess but independently - of course!

-This program can be easily generalized for more than 6-digit numbers
but you'll have to wait a relatively long time if you want to play with 10-digit numbers
-The following M-code routine does the main job in at most 0.25 second

2°) A Micro-Code Routine

Code Mnemonic

0BF    "?"                             I've called this routine "MN?"
00E    "N"
00D    "M"
2A0    SETDEC                   the first executable word
0F8    READ 3(X)
046    C=0 S&X
10E    A=C ALL
0B8    READ 2(Y)
046    C=0 S&X
02E    B=0 ALL
35C   PT=12
362    ?A#C @PT
057    JC +0A
310    LD@PT- C
3DC   PT=PT+1
0BA   A<>C M
350    LD@PT- D
3DC   PT=PT+1
0BA   A<>C M
0FA   C<>B M
23A   C=C+1 M
0FA   C<>B M
3D4   PT=PT-1
2E2   ?C#0 @PT
39F   JC -0D
0EE   C<>B ALL
0BC   RCR 5
2DC   PT=13
2E2   ?C#0 @PT
01B   JNC +03
33C   RCR 1
226   C=C+1 S&X
0E8   WRIT 3(X)                   here, X-register = the number of well-placed digits
04E   C=0 ALL
0EE   C<>B ALL
130    LDI S&X
013    CON: 19
3D4   PT=PT-1
2E2   ?C#0 @PT
04F   JC +09
0EE   C<>B ALL
0BC   RCR 5
2FE   ?C#0? MS
01B   JNC +03
33C   RCR 1
226    C=C+1 S&X
0A8   WRIT 2(Y)                  here, Y-register = the number of digits in a wrong position
3E0    RTN                            the routine always stops here
362    ?A#C @PT
057    JC +0A
310    LD@PT- C
3DC   PT=PT+1
0BA   A<>C M
350    LD@PT- D
3DC   PT=PT+1
0BA   A<>C M
0EE    C<>B ALL
23A    C=C+1 M
0EE    C<>B ALL
0AE   A<>C ALL
2FC   RCR 13
0AE   A<>C ALL
266    C=C-1 S&X
327    JC -1C
383    JNC -10

      STACK        INPUTS      OUTPUTS

           Y             y             N

           X             x             M

where M = number of well placed digits
N = number of digits in a wrong location

-Registers L Z T and synthetic registers are unchanged

Example:

   1234567791 ENTER^
   2134567891 XEQ "MN?" gives    7       3 4 5 6 7 9 1 ( the last "1" ) are well placed
                                             X<>Y   2       2 1 ( the 2 first digits ) are in a wrong location

Notes:

-Key in the codes very carefully!
-This routine gives exact results if all the digits are different from 0
-But whatever the inputs - any real number , alpha data or even non-standard bit patterns - there is no risk of "crash"
-In this case, however, the outputs ( which are always integers between 0 and 10 ) may be wrong.
-The execution time is at most 0.25 second.

3°) Program#2 ( from 1- to 10-digit numbers )

-With this program, your first guess determines the number of digits of the hidden number ( from 1 to 10 ).

Data Registers: • R00 = pseudo-random numbers ( This register is to be initialized before executing "MMD2" )

R01 = hidden number
R02 = number of guesses R03 = number of digits

Flag: F29
Subroutine: "MN?" the M-code routine listed in §2

01 LBL "MMD2"
02 FIX 0
03 CF 29
04 CLA                              If you don't have a X-Functions module, replace lines 04 to 06 by       ENTER^   LOG   INT   1   +
05 ARCL X                        but in this case, your first guess must be different from   999999999    if you play with 9-digit numbers
06 ALENG                                                                                  and smaller than   9999999989 --------------- 10-digit numbers
07 STO 02                         because roundoff-errors would miscalculate the number of digits!
08 STO 03
09 CLX
10 LBL 00                         Lines 09 thru 25 computes the mystery number
11 10
12 *
13 RCL 00
14 R-D
15 FRC
16 STO 00
17 9                                   If, for instance, you want to use digits from 1 to 7 only, replace this line by 7
18 *
19 INT
20 1
21 +
22 +
23 DSE 02
24 GTO 00
25 STO 01
26 X<>Y
27 LBL 01
28 CLA
29 ARCL X
30 ISG 02
31 CLX
32 RCL 01
33 MN?                           the M-code routine
34 RCL 03
35 X=Y?
36 GTO 02
37 "~: "                            append : space
38 ARCL Y
39 "~-"                            append -
40 ARCL Z
41 PROMPT
42 GTO 01
43 LBL 02
44 "~//"                           append / /
45 ARCL 02
46 FIX 4
47 SF 29
48 AVIEW
49 END

( 83 bytes / SIZE 004 )

Example: 1 STO 00 and suppose you want to play with 7-digit numbers

   1111111   XEQ "MMD2" >>>>      "1111111: 1-0"               there is one "1"
   1222222           R/S                           "1222222: 0-1"               the "1" is in wrong position and there is no "2"
   3133333           R/S                           "3133333: 2-1"               2 digits are in right positions 1 digit is in a wrong position. There are two "3"s
   3413444           R/S                           "3413444: 2-2"               2 -------------------------- 2 digits are in a ------------ there is one "4"
   3451355           R/S                           "3451355: 1-3"               1 ----- is ---------------- 3 -------------------------- there is no "5"
   3314666           R/S                           "3314666: 1-4"               1 ------------------------- 4 -------------------------- there is one "6"
   4613377           R/S                           "4613377: 0-5"               4 6 1 3 3 are in a wrong location. There is no "7"
   3866431           R/S                           "3866431: 2-3"               2 digits are in a right position, 3 in a wrong position. There is no "8"
   3936149           R/S                           "3936149: 4-3"               4 ------------------------------------------------- There are two "9"s
   3936914           R/S                           "3936914 / / 10"               you've found the hidden number in 10 guesses.

-Unlike "MMD", "MMD2" displays "M-N" after your guess to mean that M digits are in right positions and N digits are in wrong positions.
-Using "*" & "/" would be difficult to read for more than 6-digit numbers.
-The hidden number is computed after your first guess but - of course - independently, except for the number of its digits.
-After your first guess, all your guesses must have the same number of digits: this program does not check!

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