Digits for fun TRS-80 listing, listed 11-25-2005

    5 ' Programmed fun #1 by Ross A. Wirth
   10 ' Title -- 12 digits of fun
   15 ' Sample solution using recursive calls
   20 ' 
   25 AN=26
   30 L=0:F2$="##":F3$="###":C=0:AC=0:TC=0:J=0:X$="   ":X=0:Y=0
   35 DIM I(12),A(220,12),SP(12)
   40 CLS
   45 I(0)=0
   47 GOSUB 400 ' setup screen
   50 GOSUB 100
   55 CLS
   57 PRINT "The 12 digit answers are:"
   58 PRINT
   60 FOR J=1 TO TC
   61  L=J
   62  IF L>220 THEN L=L-220:GOTO 85
   63  PRINT J; ":  ";
   65  FOR L=1 TO 12
   70   PRINT A(J,L);
   75  NEXT
   80  PRINT:PRINT
   85 NEXT
   87 PRINT TC;" answers"
   90 END
  100 L=L+1
  105 PRINT @7," ";:PRINT USING F3$;L;
  110 I(L)=0
  115 I(L)=I(L)+1
  117 GOSUB 180:PRINT@SP(L)," ";:PRINT USING F2$;I(L);
  118 IF I(L)>12 THEN 333

  120 ' test to see if digit is already used
  130 C=0
  140 FOR J=0 TO (L-1)
  150  IF I(L)=I(J) THEN C=C+1
  160 NEXT
  170 IF C>0 THEN 330
  173 GOTO 270

  175 '  test to see how "26" is formed
  180 ON L GOTO 250,250,250,190,250,250,200,205,250,215,250,220
  190 X=I(1) +I(2) +I(3) +I(4) -AN:GOSUB 700:GOTO 250
  200 X=I(2) +I(3) +I(6) +I(7) -AN:GOSUB 700:GOTO 250
  205 X=I(5) +I(6) +I(7) +I(8) -AN:GOSUB 700
  210 X=I(1) +I(4) +I(5) +I(8) -AN:GOSUB 700:GOTO 250
  215 X=I(9) +I(2) +I(6) +I(10)-AN:GOSUB 700:GOTO 250
  220 X=I(11)+I(3) +I(7) +I(12)-AN:GOSUB 700
  230 X=I(9) +I(10)+I(11)+I(12)-AN:GOSUB 700
  250 RETURN
  270 IF L=12 THEN 310
  280 GOSUB 100
  290 GOTO 330

  300 ' new answer found
  310 AC=AC+1:TC=TC+1:PRINT@20,TC;
  312 IF AC>220 THEN AC=1
  313 PRINT@71," ";:PRINT USING F3$;AC;
  315 FOR II=1 TO 12
  320  A(AC,II)=I(II)
  325 NEXT
  330 IF I(L)<12 THEN 115
  333 I(L)=0
  335 PRINT@SP(L)," ";:PRINT USING F2$;I(L);
  340 L=L-1 ' back out of the recursion
  345 PRINT@7," ";:PRINT USING F3$;L;
  350 RETURN

  400 ' setup screen
  410 DATA 283,475,667,859,294,486
  420 DATA 678,870,464,497,656,689
  430 FOR I=1 TO 12:READ SP(I):NEXT
  440 DATA A1,B2,B3,A4,A5,B6,B7,A8,C9,C10,C11,C12
  450 FOR I=1 TO 12
  460  READ X$
  470  PRINT@(SP(I)-67),X$;
  475 NEXT
  480 FOR X=24 TO 113
  490  FOR Y=7 TO 43 STEP 9
  495   IF (X>45)AND(X<92) THEN 510
  500   IF (Y=7)OR(Y=43) THEN 520
  510   SET(X,Y)
  520  NEXT
  530 NEXT
  540 FOR Y=8 TO 42
  550  FOR X=24 TO 112 STEP 22
  555   IF (Y>15)AND(Y<35) THEN 570
  560   IF (X<46)OR(X>91) THEN 580
  570   SET(X,Y):SET(X+1,Y)
  580  NEXT
  590 NEXT
  600 PRINT@0,"Level";
  610 PRINT@64,"Answers   0";
  620 RETURN
  700 IF X=0 THEN 750
  710 IF X>0 THEN I(L)=13:GOTO 750
  720 X=-X
  730 IF I(L)>X THEN I(L)=13 ELSE I(L)=I(L)+X
  750 RETURN