5 'PFACTORS.BAS  -- for GWBasic or QBAsic
10 GOTO 500
100  LOCATE 15, 15: PRINT "Number to be factored is ";
110 INPUT N
120 IF N <= 1 THEN 300
130 LOCATE 20, 1: PRINT "                                                                                                                         "
150 B = 0
160 FOR I = 2 TO N / 2
170 IF N / I > INT(N / I) THEN 250
180 B = B + 1
190 IF B > 1 THEN 210
200 LOCATE 20, 1: PRINT "Prime factors of "; N; " are ";
210 PRINT I;
220 N = N / I
230 IF N = 1 THEN 280
240 I = I - 1
250 NEXT I
270 LOCATE 20, 1: PRINT N; " is a prime number "
280 LOCATE 15, 26: PRINT "                                                   "
290 GOTO 100
300 CLS : KEY ON: END
310 '
500 CLS
510 KEY OFF
520 TOPSIDE$ = CHR$(201) + STRING$(29, CHR$(205)) + CHR$(187)
530 BOTTOM$ = CHR$(200) + STRING$(29, CHR$(205)) + CHR$(188)
540 TITLE$ = " PRIME FACTORS OF AN INTEGER "
550 TITLE1$ = "                             "
560 TITLE2$ = "    H. Heinz   Sept. 1985    "
570 PRINT TAB(23); TOPSIDE$
580 PRINT TAB(23); CHR$(186); TITLE$; CHR$(186)
590 PRINT TAB(23); CHR$(186); TITLE1$; CHR$(186)
600 PRINT TAB(23); CHR$(186); TITLE2$; CHR$(186)
610 PRINT TAB(23); BOTTOM$
620 PRINT
630 PRINT TAB(21); "This program finds the Prime Factors"
640 PRINT TAB(21); "of the number input. Enter 1 to quit."
650 PRINT TAB(21); "Your integer may contain up to 7 digits."
655 PRINT TAB(21); "Enter 0 to end program."
660 GOTO 100
670 'USES GW BASIC
680 'NAME IS PFACTORS.BAS
690 'CAN'T USE DOUBLE PRECISION BECAUSE 'FOR' WON'T WORK IN D.P.
700 'TRY 9699690,7864320