BAGELS
Багель
David Ahl, 1973
Three digits, all different, and three words to tell you how close you are. ФЕРМИ for a digit in the right place, ПИКО for a digit in the wrong place, БАГЕЛЬ for nothing at all. Twelve guesses. The whole game is the gap between what those words tell you and what you need to know.
- sectors
- 20-24
- source lines
- 82
- guesses
- 12
Run this disk · The image, 256,256 bytes
Why this one matters
BAGELS reached everyone through David Ahl's 1973 collection of BASIC games, and it stayed in the listing books afterward because it needs so little: no board, no pieces, no picture on the screen. A player, a secret, and three words. It is the deduction game that Mastermind sells in a box, without the box. What made it worth typing in was that it hands you less information than the problem looks like it requires, and turns out to be solvable anyway. That is a lesson about search rather than luck, and a lot of people met it here first.
Why it is worth having here
Everything I know about this dialect I learned from a payroll program and a database suite out of a planning institute. The tokens were shaped to add up wages and print a column of roubles. BAGELS asks the same instrument to keep a secret and answer questions about it in single words, in uppercase Cyrillic, on a terminal with no lowercase and no graphics at all. ФЕРМИ and ПИКО are the physicists' names the American original used, carried across untranslated, and they sit in Cyrillic exactly as strangely as they sat in English.
What it cost the interpreter
BAGELS runs on counters, and counters end their statements with a subtraction. That is where my old rule broke. I had been reading the minus token with a lookahead that turned V01 = V01 - 1 at the end of a payload into V01 plus a stray literal of minus one. The correct rule is shorter and duller: after an operand the token is binary minus, otherwise it opens a negative literal. The payroll software never made that difference visible. Rerunning it against the printed sheet at 212.30 roubles afterward confirmed the correction cost the corpus nothing.
What this disk is not
This disk is not a find. I wrote it in 2026, along with the assembler that builds it. No Soviet games disk was ever recovered, and nothing here reprints anyone's listing. What is old is the mechanic, common property since the early seventies. What is new is every byte of the Russian code and every decision inside it. If that sentence goes missing, somebody later holds up an invention as evidence, and at that point the whole project deserves to fall over. So it goes on every page, including this one.
What I checked
BAGELS, guess 1-2-3 against secret 9-0-7 returns "БАГЕЛЬ" correctly, then a hit.
What this does not show
The seed is fixed at 37, because no clock or timer atom is attested, so the same secret comes up on every run. Historically that is authentic, which is why so many early BASIC games asked you to type a number first, but it does mean the disk plays itself out the same way twice. What is tested is the emulator, not the hardware; whether a surviving Iskra-226 accepts these bytes is still open.
Where to read more
- Bagels in BASIC Computer Games The listing by D. Resek and P. Rowe, three digits and three words, printed in Ahl's 1978 collection.
- BASIC Computer Games, the whole book The 1978 collection scanned end to end, six of my seven canon titles among them.
- BAGELS.bas, the source Eighty-two lines, and the counters at the end of them are where my rule for minus came apart.
- The classics pack All seven on one disk, with the sector map and the four interpreter faults they turned up between them.
The source
BAGELS.bas, 82 lines, assembled onto the image with iskra_asm.py
82 lines of BASIC
10 REM BAGELS 20 PRINT "*** БАГЕЛЬ ***" 30 PRINT "Я ЗАГАДАЛ 3 РАЗНЫЕ ЦИФРЫ." 40 PRINT "ФЕРМИ - ЦИФРА НА СВОЕМ МЕСТЕ." 50 PRINT "ПИКО - ЦИФРА ЕСТЬ, НО НЕ ТАМ." 60 PRINT "БАГЕЛЬ - НЕТ НИ ОДНОЙ." 70 V50 = 37 80 GOSUB 900 81 V01 = V50 / 10 82 GOSUB 950 83 V07 = V60 84 GOSUB 900 85 V01 = V50 / 10 86 GOSUB 950 87 V08 = V60 88 IF V08 = V07 GOTO 84 89 GOSUB 900 90 V01 = V50 / 10 91 GOSUB 950 92 V09 = V60 93 IF V09 = V07 GOTO 89 94 IF V09 = V08 GOTO 89 100 V10 = 0 110 V10 = V10 + 1 120 PRINT "--- ПОПЫТКА";V10 130 PRINT "ТРИ ЦИФРЫ ПО ОДНОЙ" 140 INPUT V04 141 INPUT V05 142 INPUT V06 150 V11 = 0 160 V12 = 0 170 IF V04 = V07 GOTO 175 171 GOTO 180 175 V11 = V11 + 1 180 IF V05 = V08 GOTO 185 181 GOTO 190 185 V11 = V11 + 1 190 IF V06 = V09 GOTO 195 191 GOTO 200 195 V11 = V11 + 1 200 IF V04 = V08 GOTO 205 201 GOTO 210 205 V12 = V12 + 1 210 IF V04 = V09 GOTO 215 211 GOTO 220 215 V12 = V12 + 1 220 IF V05 = V07 GOTO 225 221 GOTO 230 225 V12 = V12 + 1 230 IF V05 = V09 GOTO 235 231 GOTO 240 235 V12 = V12 + 1 240 IF V06 = V07 GOTO 245 241 GOTO 250 245 V12 = V12 + 1 250 IF V06 = V08 GOTO 255 251 GOTO 260 255 V12 = V12 + 1 260 IF V11 = 3 GOTO 400 270 IF V11 > 0 GOTO 280 271 IF V12 > 0 GOTO 280 272 PRINT "БАГЕЛЬ" 273 GOTO 300 280 PRINT "ФЕРМИ";V11;" ПИКО";V12 300 IF V10 < 12 GOTO 110 310 PRINT "*** ПОПЫТКИ КОНЧИЛИСЬ ***" 320 PRINT "ЧИСЛО БЫЛО";V07;V08;V09 330 END 400 PRINT "*** УГАДАЛИ ЗА";V10;" ПОПЫТОК! ***" 410 END 900 V50 = V50 * 21 910 V50 = V50 + 13 920 IF V50 < 100 GOTO 940 930 V50 = V50 - 100 935 GOTO 920 940 RETURN 950 V60 = 0 960 IF V01 < 1 GOTO 990 970 V60 = V60 + 1 980 V01 = V01 - 1 985 GOTO 960 990 RETURN