线性筛法

const  

maxn=1000000007;

var  

bz:array[1..2000000] of boolean;  

ss:array[0..1000000] of longint;  

i,j,n,t:longint;

begin  

readln(n);  

fillchar(bz,sizeof(bz),true);  

for i:=2 to n do  

begin  

if bz[i] then  

begin  

inc(ss[0]);  

ss[ss[0]]:=i;  

end;  

for j:=1 to ss[0] do  

begin  

if n/ss[j]<i then break;  

bz[i*ss[j]]:=false;  

if i mod ss[j]=0 then break;  

end;  

end;  

for i:=1 to ss[0] do write(ss[i],' ');

end.