(*$B- Aufgabe2.5*)
PROGRAM sieb ;
VAR i,j,n,k,logn : integer;
    p : ARRAY [1..1000] OF boolean;
    tf : text; stri : string[20];

FUNCTION log(x:real):real; BEGIN log := ln(x)/ln(10) END;

BEGIN
   writeln('Wohin mit der Ausgabe');
   readln (stri); assign(tf,stri); rewrite (tf);
   writeln ('Bis wohin Primzahlen rechnen');
   read (n); logn := round(log(n))+2; k :=0;
   FOR i:=2 TO n DO p[i]:= true; i:= 2;
   REPEAT
      IF p[i] THEN
      BEGIN
         write (tf,i:logn); k := k+1;
         IF k MOD 10 =  0 THEN writeln(tf);
         j:= 2*i;
         WHILE j <= n DO BEGIN p[j]:= false; j:= j+i END;
      END;
      i:= i+1;
   UNTIL i = n;
   close(tf)
END.