1 ! PROGRAM NAME --> G C F  -- BY BOB HUNTSMAN
10 DIM B$(7%):B$(1%)="EASY":B$(2%)="MEDIUM":B$(3%)="HARD":
	B$(4%)="WRONG":B$(5%)="RIGHT":B$(6%)="LOW":B$(7%)="HIGH"
11 DIM B2$(3%),B2%(3%):B2$(1%)="LET'S START WITH":B2$(2%)=
	"NOW SOME":B2$(3%)="FINALLY, SOME":B2%(1%)=5%:B2%(2%)=3%:
	B2%(3%)=2%:B2%(0%)=5%:B%=0%
12 OPEN "KB:" AS FILE 1%:INPUT #1%, "NAME (CR)---> ";N$:
	V9$=SYS(CHR$(3%)):
	FIELD #1%,K% AS Q$,1% AS M3$(K%) FOR K%=0% TO 10%:RANDOM
15 RANDOM:DIM A%(30%)
17 DIM H%(15%):H%(1%)=1%:H%(K%)=2% FOR K%=2% TO 5%
18 H%(6%)=1%:H%(K%)=3% FOR K%=7% TO 10%
19 H%(11%)=1%:H%(K%)=5% FOR K%=12% TO 15%
30 PRINT "ENTER 'I' FOR INSTRUCTIONS:";:GOSUB 29000:PRINT M4$:GOTO 135
	IF M4$<>"I"
40 PRINT:PRINT "THIS IS PROGRAM #2, NAME -GCF- .  IT WILL DRILL YOU ";
	"ON YOUR"
50 PRINT "ABILITY TO CALCULATE GREATEST COMMON FACTORS.  TO PASS";
	" THIS PROGRAM,"
55 PRINT "YOU MUST ANSWER 5 EASY PROBLEMS, 3 MEDIUM ";
	"PROBLEMS, AND 2 HARD"
60 PRINT "PROBLEMS.  YOU'LL BE GIVEN THREE TRIES TO ANSWER EACH ";
	"PROBLEM; HOWEVER"
65 PRINT "ONLY PROBLEMS ANSWERED CORRECTLY THE FIRST TRY ARE ";
	"SCORED AS CORRECT"
70 PRINT "ANSWERS.  YOU MUST GET 80% OF THE EASY ONES CORRECT, 70% ";
	"OF THE MEDIUM"
75 PRINT "ONES CORRECT AND 50% OF THE HARD ONES CORRECT (THEY ARE ";
	"R E A L L Y"
85 PRINT "HARD) IN ORDER TO PASS.  IF YOU PASS, THE COMPUTER WILL TELL";
	" YOU AND"
90 PRINT "ALLOW YOU TO GO ON TO PROGRAM #3!  BY THE WAY, IF YOU WANT"
	;" TO KNOW HOW"
95 PRINT "YOU'RE DOING ENTER '?' WHEN ASKED FOR YOUR ANSWER.  IF YOU ";
	"GIVE UP,"
100 PRINT "ENTER 'Q' FOR YOUR ANSWER AND THE PROGRAM WILL TERMINATE!!":
	PRINT:PRINT
110 GOTO 135
130 GOTO 1300 IF X%(B%+3%)=0%:GOTO 1300 IF B2%(B%)>X%(B%):
	GOTO 1300 IF 100%*X%(B%)/X%(B%+3%)<35%+15%*(4%-B%)
135 GOTO 1200 IF B%=3%:B%=B%+1%:PRINT:PRINT B2$(B%);" ";B$(B%);" ONES:":
	PRINT:GOTO 130
200 GOTO 130 IF F6%=0%:PRINT:F6%=0%:GOTO 230 IF B%:PRINT
	"GO BACK AND REDO PROGRAM #1, I N T R O !!!":
	GOTO 32000
230 PRINT "REDO THE ";B$(B%);" PROBLEMS!!":
	X%(B%),X%(B%+3%),X%(B%+1%),X%(B%+4%)=0%:GOTO 200
500 A1%=B3%:GOSUB 600:B%(K%)=A%(K%) FOR K%=0% TO A%(0%):B1$=A1$:A1%=A%:GOSUB 600
505 PRINT "THE PRIME FACTORS OF THE FIRST NUMBER ARE:":PRINT A1$
510 PRINT:PRINT "THE PRIME FACTORS OF THE SECOND NUMBER ARE:":PRINT B1$:
	PRINT:RETURN
550 PRINT "THE GREATEST COMMON FACTOR OF THESE TWO NUMBERS EQUALS THE":
	PRINT "PRODUCT OF THE PRIME FACTORS THE TWO ";
	"NUMBERS HAVE IN COMMON.  -- THAT"
555 PRINT "IS THE PRODUCT OF THE INTERSECTION OF THEIR PRIME NUMBERS.":
	PRINT:A1%=C%:GOSUB 600:GOTO 590 IF A%(0%)=1%
580 PRINT "THE FACTOR IN THE INTERSECTION ARE:":PRINT:PRINT A1$:PRINT:
	PRINT:RETURN
590 PRINT "THE TWO NUMBERS ARE RELATIVELY PRIME.  THE GREATEST ";
	"COMMON FACTOR OF":PRINT "ANY TWO NUMBERS WHICH ARE ";
	"RELATIVELY PRIME IS ALWAYS THE SAME":
	PRINT "NUMBER.":PRINT:RETURN
600 D%=2%:A%(0%),A%(1%)=1%
610 IF A1%/D%*D%=A1% THEN A%(0%)=A%(0%)+1%:A%(A%(0%))=D%:A1%=A1%/D%:
	GOTO 610
620 D%=D%+2%:D%=3% IF D%=4%:GOTO 630 IF D%>A1%:GOTO 610
630 A1$=FNN$(1%):A1$=A1$+","+FNN$(A%(K%)) FOR K%=2% TO A%(0%):RETURN
640 DEF FNN$(V%)=MID(NUM$(V%),2%,LEN(NUM$(V%))-2%)
800 X3%=X3%+1%:H5%=H5%+1% IF B%=3%:X%=X%+1%:
	X%(B%+3%)=X%(B%+3%)+1%:X%(B%)=X%(B%)+1% IF E%=3%
810 RETURN IF E%=3% OR X%(B%+3%)<6%+B2%(B%):F6%=1%:PRINT
	:B%=B%-1%:PRINT N$;" -- YOU ARE NOT DOING VERY WELL ON ";
	"THESE PROBLEMS.  YOU MUST":RETURN
900 D%=0%:D1%=INT(LOG10(C%))+1%:FOR K1%=1% TO D1%
910 GOSUB 29000:GOTO 920 IF M4$="?":GOTO 940 IF M4$="Q":
	M%=ASCII(M4$):GOTO 910 IF M%=32% AND D%=0%:RETURN
	IF M%=13% OR M%=32%:GOTO 910 IF M%<48% OR M%>57%:
	D%=D%*10%+M%-48%:PRINT M4$;:NEXT K1%:RETURN  
920 F4%=0%:F4%=1% IF X%(K%) FOR K%=4% TO 6%:GOTO 910 IF F4%=0%
930 X%=POS(1%):PRINT M4$;:A1%=A%:B1%=B%:GOSUB 32005:A%=A1%:B%=B1%:
	PRINT TAB(X%-4%);"---> ";:GOTO 900
940 PRINT:PRINT:PRINT "SORRY, ";N$;" -- YOU DO NOT PASS. . .":
	GOTO 32000
1000 DEF FNR%(V%,V1%)
1010 V2%=V1%-V%+1%:V3%=INT(1000%*RND):V3%=V3%-V3%/V2%*V2%+V%:FNR%=V3%
1020 FNEND
1100 DEF FNX%=X%(1%)+X%(2%)+X%(3%)
1200 PRINT:PRINT "CONGRATULATIONS, ";N$;".  YOU HAVE SUCCESSFULLY PASSED"
1210 PRINT "THE REQUIREMENTS OF PROGRAM #2!!  YOU MAY NOW GO ON"
1220 PRINT "TO PROGRAM #3, NAMED -REDUCE-!!":PRINT:GOTO 32000
1300 H%=2%:I%=39%:IF B%=2% THEN H%=40%:I%=100%
1305 IF B%=3% THEN H%=80%:I%=364%
1310 R%=FNR%(1%,5%):IF B%=4% THEN I%=999%
1315 A%=FNR%(H%,I%):B3%=FNR%(H%,I%):GOTO 1315 IF FNC%(A%,B3%)<H%((B%-1%)*5%+R%)
1316 GOTO 1315 IF R%<>5% AND A%=B3%
1317 PRINT "THE GCF OF";A%;"AND";B3%;"IS";TAB(25%);"--> ";
1320 C%=FNC%(A%,B3%):E%=3%
1325 PRINT "ANSWER:";:GOSUB 900:PRINT TAB(44%);:GOTO 1350 IF D%=C%:
	F%=6%:F%=7% IF D%>C%:PRINT "NO, ";N$;", YOU'RE TOO ";
	B$(F%);"."
1327 GOSUB 500 IF E%=3%:GOSUB 550 IF E%=2%
1330 IF E%>1% THEN PRINT "TRY AGAIN!!  [";A%;"&";B3%;"]":
	E%=E%-1%:GOTO 1325
1335 E%=0%:PRINT "SORRY, ";N$;", THREE TRIES IS ALL YOU GET!!":
	PRINT "THE CORRECT ANSWER IS -->";C%:PRINT:GOSUB 800:GOTO 200
1350 PRINT "CORRECT!!":GOSUB 800:GOTO 200
1600 DEF FNC%(V%,V1%)
1610 E%=1%:D5%=0%
1625 D5%=D5%+2%:D5%=3% IF D5%=4%:IF D5%>V% OR D5%>V1% THEN FNC%=E%:GOTO 1640
1630 IF V%/D5%*D5%=V% AND V1%/D5%*D5%=V1% THEN E%=E%*D5%:V%=V%/D5%:
	V1%=V1%/D5%:GOTO 1630
1635 V%=FNQ%(V%,D5%):V1%=FNQ%(V1%,D5%):GOTO 1625
1640 FNEND
1660 DEF FNQ%(V2%,V3%)
1665 IF V2%/V3%=V3%=V2% THEN V2%=V2%/V3%:GOTO 1665
1670 FNQ%=V2%
1675 FNEND
29000 GOTO 29100 IF M3%=Z3%:M4$=M3$(M3%):M3%=M3%+1%:RETURN
29100 M3%=0%:V9$=SYS(CHR$(4%)):GET #1%:Z3%=RECOUNT:GOTO 29000
32000 PRINT:PRINT "GREATEST COMMON FACTOR":F3%=1%
32005 U$="\    \ - ## OUT OF ## ---> ###%":V9$=SYS(CHR$(2%))
	UNLESS F3%=0%
32007 PRINT:PRINT N$;" -- HERE ARE YOUR SCORES:":PRINT
32010 FOR K%=1% TO 3%:GOTO 32100 IF X%(K%+3%)=0%:PRINTUSING U$,
	B$(K%),X%(K%),X%(K%+3%),100%*X%(K%)/X%(K%+3%)
32100 NEXT K%
32220 B%=0%:B%=B%+X%(K%) FOR K%=4% TO 6%:A%=0%:A%=A%+X%(K%) 
       FOR K%=1% TO 3%:A%=100%*A%/B%
32225 IF F3%=0% THEN PRINT:PRINT "CUMULATIVE-->";A%:PRINT:RETURN
32230 B%=0%:B%=1% IF A%>60%:B%=2% IF A%>89%:DIM Z$(2%)
32240 Z$(0%)=", YOU DEFINITELY NEED MUCH MORE"
	+ " PRACTICE!!":Z$(1%)=", YOU DID ABOUT AVERAGE"
	+ " -- BUT YOU STILL NEED MORE PRACTICE!!"
32250 Z$(2%)=" -- GREAT -- YOU SEEM TO UNDERSTAND"
	+ " THESE PROBLEMS VERY WELL!!"
32260 A$=NUM$(A%):PRINT:PRINT "YOUR CUMULATIVE SCORE IS";
       LEFT(A$,LEN(A$)-1%);"%.":PRINT
32270 PRINT N$+Z$(B%):PRINT
32767 END