500 IF PRTFLG=1 THEN OPEN "LPT1:" FOR OUTPUT AS #2
510 IF PRTFLG=2 THEN INPUT "Enter the file which is to recieve the output: ",A$:OPEN DISK$+A$ FOR OUTPUT AS #2:PRINT
520 PAL$="":PRINT "Enter the sequence to be searched for: ";
530 A$=INKEY$:IF A$="" THEN 530
540 IF A$="A" OR A$="a" OR A$="1" THEN PAL$=PAL$+"A":PRINT "A";:GOTO 530
550 IF A$="C" OR A$="c" OR A$="2" THEN PAL$=PAL$+"C":PRINT "C";:GOTO 530
560 IF A$="G" OR A$="g" OR A$="3" THEN PAL$=PAL$+"G":PRINT "G";:GOTO 530
570 IF A$="T" OR A$="t" OR A$="4" THEN PAL$=PAL$+"T":PRINT "T";:GOTO 530
580 IF A$="N" OR A$="n" OR A$="5" THEN PAL$=PAL$+"N":PRINT "N";:GOTO 530
590 IF A$=CHR$(13) THEN PRINT ELSE BEEP:GOTO 530
600 PRINT:PRINT:INPUT "Enter the minimum homology acceptable (%): ",HOMO
610 L=LEN(PAL$):HOMO=L*HOMO/100
620 IF PRTFLG THEN PRINT #2,TITLE$:PRINT #2,CHR$(10);"Sequence searched for: ";PAL$:PRINT #2,STRING$(2,10);"Position     Sequence found     Homology"
630 F=8:E=LENGTH-L+1:PRINT:PRINT:PRINT "Position     Sequence found     Homology"
640 FOR I=1 TO E
650 J=1:A=L
660 A$=MID$(PAL$,J,1):IF A$="N" GOTO 690
670 IF A$<>MID$(SEQ$((I+J-2)\250+1),(I+J-2) MOD 250+1,1) THEN A=A-1
680 IF A