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Magnum One
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Magnum One (Mid-American Digital) (Disc Manufacturing).iso
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d12
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util307.arc
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CIPHER.BAS
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BASIC Source File
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1987-03-04
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640b
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23 lines
100 DEFINT A-Z
110 INPUT "INPUT FILENAME? ",INFILE$
120 INPUT "OUTPUT FILENAME? ",OUTFILE$
130 INPUT "ENTER E=ENCRYPT,D=DECRYPT: ",S$
140 S=1:IF S$="D" OR S$="d" THEN S=-1
150 INPUT "ENTER YOUR KEY: ",KY$
160 OPEN INFILE$ FOR INPUT AS #1
170 OPEN OUTFILE$ FOR OUTPUT AS #2
180 KIX=0
190 IF EOF(1) THEN 280
200 C=ASC(INPUT$(1,#1))
210 IF C<&H20 OR C>&H7A THEN 260
220 KIX=KIX+1:IF KIX>LEN(KY$) THEN KIX=1
230 C$=MID$(KY$,KIX,1):C=C+S*ASC(C$)
240 IF C<&H20 THEN C=C+&H5B
250 IF C>&H7A THEN C=C-&H5B
260 PRINT #2,CHR$(C);
270 GOTO 190
280 CLOSE #1
290 CLOSE #2
300 SYSTEM
<&H20 THEN C=C+&H5B
250 IF C>&H7A THEN C=C-&H5B