PROGRAM BAGELS;
TYPE
    INT_ARRAY = ARRAY [1..3] OF INTEGER;
    PINT_ARRAY = ^INT_ARRAY;

FUNCTION ASK_QUESTION(PROMPT:STRING):STRING;
VAR
   ANS:STRING;
   GOT_ANS:BOOLEAN;
   I:INTEGER;
BEGIN
     GOT_ANS := FALSE;
     WHILE(GOT_ANS = FALSE) DO
     BEGIN
          WRITELN(PROMPT,'? ');
          READLN(ANS);
          IF ANS = '' THEN
          BEGIN
             WRITELN('PLEASE ANSWER THE QUESTION.');
          END
          ELSE
          BEGIN
               FOR I := 1 TO LENGTH(ANS) DO
                   ANS[I] := UPCASE(ANS[I]);
               GOT_ANS := TRUE;
          END;
     END;
     ASK_QUESTION := ANS
END;

FUNCTION IS_AN_INT(INPUT:STRING):BOOLEAN;
VAR
   VALUE,CODE:INTEGER;
BEGIN
     VAL(INPUT,VALUE,CODE);
     IS_AN_INT := CODE = 0;
END;

FUNCTION GET_INT_INPUT(PROMPT:STRING):INTEGER;
VAR
   ANS:STRING;
   GOT_ANS:BOOLEAN;
   VALUE,CODE:INTEGER;
BEGIN
     GOT_ANS := FALSE;
     WHILE(GOT_ANS = FALSE) DO
     BEGIN
          WRITELN(PROMPT, '');
          READLN(ANS);
          IF IS_AN_INT(ANS) THEN
          BEGIN
               VAL(ANS,VALUE,CODE);
               GOT_ANS := TRUE;
          END
          ELSE
              WRITELN('YOU DID NOT ENTER AN INTEGER.');
     END;
     GET_INT_INPUT := VALUE;
END;

FUNCTION ASK_TO_PLAY_AGAIN:BOOLEAN;
VAR
   GOT_ANS,ANSWER:BOOLEAN;
   ANS:STRING;
BEGIN
     GOT_ANS := FALSE;
     WHILE(GOT_ANS = FALSE) DO
     BEGIN
          ANS := ASK_QUESTION('DO YOU WANT TO PLAY AGAIN');
          IF ANS = 'YES' THEN
          BEGIN
               GOT_ANS := TRUE;
               ANSWER := TRUE;
          END
          ELSE IF ANS = 'Y' THEN
          BEGIN
               GOT_ANS := TRUE;
               ANSWER := TRUE;
          END
          ELSE IF ANS = 'NO' THEN
          BEGIN
               GOT_ANS := TRUE;
               ANSWER := FALSE;
          END
          ELSE IF ANS = 'N' THEN
          BEGIN
               GOT_ANS := TRUE;
               ANSWER := FALSE;
          END
          ELSE
               WRITELN('PLEASE ANSWER "YES" OR "NO".');
     END;
     ASK_TO_PLAY_AGAIN := ANSWER;
END;

FUNCTION ASK_TO_SEE_THE_RULES:BOOLEAN;
VAR
   GOT_ANS,ANSWER:BOOLEAN;
   ANS:STRING;
BEGIN
     GOT_ANS := FALSE;
     WHILE(GOT_ANS = FALSE) DO
     BEGIN
          ANS := ASK_QUESTION('DO YOU WANT TO SEE THE RULES');
          IF ANS = 'YES' THEN
          BEGIN
               GOT_ANS := TRUE;
               ANSWER := TRUE;
          END
          ELSE IF ANS = 'Y' THEN
          BEGIN
               GOT_ANS := TRUE;
               ANSWER := TRUE;
          END
          ELSE IF ANS = 'NO' THEN
          BEGIN
               GOT_ANS := TRUE;
               ANSWER := FALSE;
          END
          ELSE IF ANS = 'N' THEN
          BEGIN
               GOT_ANS := TRUE;
               ANSWER := FALSE;
          END
          ELSE
              WRITELN('PLEASE ANSWER "YES" OR "NO".');
     END;
     ASK_TO_SEE_THE_RULES := ANSWER;
END;

FUNCTION GENERATE_RANDOM_NUMBER(MINIMUM:INTEGER;MAXIMUM:INTEGER;SHOW:BOOLEAN):INTEGER;
VAR
   VALUE:INTEGER;
BEGIN
     RANDSEED := RANDOM(12345) + 5432;
     VALUE := RANDOM(MAXIMUM) + MINIMUM;
     IF SHOW = TRUE THEN
        WRITELN(VALUE);
     GENERATE_RANDOM_NUMBER := VALUE;
END;

PROCEDURE DISPLAY_RULES;
BEGIN
     WRITELN('I WILL THINK OF A THREE-DIGIT NUMBER.  YOU WILL TRY TO');
     WRITELN('GUESS MY NUMBER AND I WILL GIVE YOU CLUES AS FOLLOWS:');
     WRITELN('  PICO   - ONE DIGIT CORRECT BUT IN THE WRONG POSITION');
     WRITELN('  FERMI  - ONE DIGIT CORRECT AND IN THE RIGHT POSITION');
     WRITELN('  BAGLES - NO DIGITS ARE CORRECT');
     WRITELN(' ');
     WRITELN('YOU GET TWENTY TRIES BEFORE YOU LOSE.');
     WRITELN(' ');
END;

FUNCTION ASK_FOR_GUESS(ATTEMPT:INTEGER):INTEGER;
VAR
   GOT_GUESS:BOOLEAN;
   RET_VAL:INTEGER;
   PROMPT:STRING;
BEGIN
     STR(ATTEMPT,PROMPT);
     GOT_GUESS := FALSE;
     WHILE(GOT_GUESS = FALSE) DO
     BEGIN
          RET_VAL := GET_INT_INPUT('GUESS #' + PROMPT);
          IF RET_VAL < 0 THEN
             WRITELN('PLEASE GUESS A NON-NEGATIVE NUMBER.')
          ELSE IF (RET_VAL < 100) OR (RET_VAL > 999) THEN
               WRITELN('PLEASE GUESS A NUMBER BETWEEN 100 AND 999.')
          ELSE
              GOT_GUESS := TRUE;
     END;
     ASK_FOR_GUESS := RET_VAL;
END;

PROCEDURE DISPLAY_GAME_OVER(NUMBER:INTEGER);
BEGIN
     WRITELN('OH WELL, THAT"S TWENTY GUESSES.');
     WRITELN('MY NUMBER WAS ',NUMBER,'.');
END;

FUNCTION MAKE_ARRAY_FROM_INTEGER(VAL_IN:INTEGER):PINT_ARRAY;
VAR
   RET_ARRAY:PINT_ARRAY;
BEGIN
     RET_ARRAY^[1] := TRUNC(VAL_IN / 100);
     RET_ARRAY^[2] := TRUNC((VAL_IN - (RET_ARRAY^[1] * 100)) / 10);
     RET_ARRAY^[3] := (VAL_IN - (RET_ARRAY^[1] * 100) - (RET_ARRAY^[2] * 10));
     MAKE_ARRAY_FROM_INTEGER := RET_ARRAY;
END;

FUNCTION MAKE_INTEGER_FROM_ARRAY(ARRAY_IN:INT_ARRAY):INTEGER;
VAR
   RET_VAL:INTEGER;
BEGIN
     RET_VAL := (ARRAY_IN[1] * 100) + (ARRAY_IN[2] * 10) + ARRAY_IN[3];
     MAKE_INTEGER_FROM_ARRAY := RET_VAL;
END;

FUNCTION CREATE_THE_NUMBER:PINT_ARRAY;
VAR
   DIGITS:PINT_ARRAY;
   GOT_DIGIT:BOOLEAN;
BEGIN
     DIGITS^[1] := GENERATE_RANDOM_NUMBER(1, 9, FALSE);
     GOT_DIGIT := FALSE;
     WHILE(GOT_DIGIT = FALSE) DO
     BEGIN
          DIGITS^[2] := GENERATE_RANDOM_NUMBER(0, 9, FALSE);
          GOT_DIGIT := (DIGITS^[2] <> DIGITS^[1]);
     END;
     GOT_DIGIT := FALSE;
     WHILE(GOT_DIGIT = FALSE) DO
     BEGIN
          DIGITS^[3] := GENERATE_RANDOM_NUMBER(0, 9, FALSE);
          GOT_DIGIT := ((DIGITS^[3] <> DIGITS^[1]) AND (DIGITS^[3] <> DIGITS^[2]));
     END;
     CREATE_THE_NUMBER := DIGITS;
END;

FUNCTION CHECK_GUESS(GUESS:INTEGER;DIGITS:INT_ARRAY):BOOLEAN;
VAR
   TEMP:PINT_ARRAY;
   VALS:INT_ARRAY;
   VALUE:INTEGER;
BEGIN
     TEMP := MAKE_ARRAY_FROM_INTEGER(GUESS);
     VALS[1] := 0;
     VALS[2] := 0;
     VALS[3] := 0;
     IF TEMP^[1] = DIGITS[1] THEN VALS[1] := 1;
     IF TEMP^[2] = DIGITS[2] THEN VALS[2] := 1;
     IF TEMP^[3] = DIGITS[3] THEN VALS[3] := 1;
     VALUE := MAKE_INTEGER_FROM_ARRAY(VALS);
     IF VALUE = 111 THEN CHECK_GUESS := TRUE
     ELSE
     BEGIN
          IF VALS[1] = 0 THEN
             IF (TEMP^[1] = DIGITS[2]) OR (TEMP^[1] = DIGITS[3]) THEN VALS[1] := 2;

          IF VALS[2] = 0 THEN
             IF (TEMP^[2] = DIGITS[1]) OR (TEMP^[2] = DIGITS[3]) THEN VALS[2] := 2;

          IF VALS[3] = 0 THEN
             IF (TEMP^[3] = DIGITS[1]) OR (TEMP^[3] = DIGITS[2]) THEN VALS[3] := 2;
          VALUE := MAKE_INTEGER_FROM_ARRAY(VALS);
          IF VALUE = 0 THEN WRITELN('BAGELS')
          ELSE
          BEGIN
               IF VALS[1] = 1 THEN WRITE('FERMI ');
               IF VALS[1] = 2 THEN WRITE('PICO ');
               IF VALS[2] = 1 THEN WRITE('FERMI ');
               IF VALS[2] = 2 THEN WRITE('PICO ');
               IF VALS[3] = 1 THEN WRITE('FERMI');
               IF VALS[3] = 2 THEN WRITE('PICO');
               WRITELN(' ');
          END;
          CHECK_GUESS := FALSE;
     END;
END;

VAR
   RUNNING,GAME_OVER:BOOLEAN;
   SCORE,GUESS,ATTEMPT,NUMBER:INTEGER;
   DIGITS:INT_ARRAY;
   ANS:STRING;
BEGIN
     WRITELN('*** BAGELS : PASCAL ***');
     RUNNING := TRUE;
     IF ASK_TO_SEE_THE_RULES = TRUE THEN
        DISPLAY_RULES;
     WHILE(RUNNING = TRUE) DO
     BEGIN
          GAME_OVER := FALSE;
          ATTEMPT := 1;
          DIGITS := CREATE_THE_NUMBER^;
          WRITELN('OK, I HAVE A NUMBER IN MIND.');
          WHILE(GAME_OVER = FALSE) DO
          BEGIN
               GUESS := ASK_FOR_GUESS(ATTEMPT);
               IF CHECK_GUESS(GUESS, DIGITS) = TRUE THEN
               BEGIN
                    WRITELN('YOU GOT IT!!!');
                    SCORE := SCORE + 1;
                    GAME_OVER := TRUE;
               END
               ELSE
               BEGIN
                    ATTEMPT := ATTEMPT + 1;
                    IF ATTEMPT > 20 THEN
                    BEGIN
                         NUMBER := MAKE_INTEGER_FROM_ARRAY(DIGITS);
                         DISPLAY_GAME_OVER(NUMBER);
                         GAME_OVER := TRUE;
                    END;
               END;
          END;
          WRITELN('*** GAME OVER ***');
          RUNNING := ASK_TO_PLAY_AGAIN;
     END;
     WRITELN('A ',SCORE,' POINT BAGELS BUFF!');
     WRITELN('HOPE YOU HAD FUN. BYE!');
     READLN(ANS);
END.