Crivello di Erastotene in GW-BASIC

Qui sotto l'implementazione del crivello di Erastotene in GW-BASIC (dettagli in https://sebcosta.altervista.org/joomla/articles/30-crivello-di-erastotene-in-gw-basic.html )

10 OPTION BASE 1
20 DIM A%(100)
30 CLS
40 INPUT "INSERISCI N=";N%
50 IF N%>100 THEN 300
60 MAXDIV%=SQR(N%)
70 FOR I=1 TO N%
80 A%(I)=0
90 NEXT
100 FOR I=2 TO MAXDIV%
110 J=I+I
120 WHILE J<=N%
130 A%(J)=1
135 J=J+I
140 WEND
150 NEXT
160 FOR I=2 TO N%
170 IF A%(I)=0 THEN PRINT I
180 NEXT
190 END
300 PRINT "N MASSIMO =";100
310 END