Второй семестр / Eratosphen

program Eratosphern;
const n=255;
type natural = 2..n;
mnosh=set of natural;
var
sieve, primes:mnosh;
next, j:natural;
begin
sieve:=[2..n]; primes:=[]; next:=2;
repeat
while not(next in sieve) do next:=next+1;
primes:= primes +[next];
j:=next;
while j<=n do
begin
sieve:=sieve-[j];
j:=j+next;
end;
{коррекция закончена}
until sieve=[];
for j:=2 to n do if (j in primes) then write (j,' ');
end.