素数打表

import java.util.Scanner;public class Main {public static void main(String[] args) {// TODO Auto-generated method stubScanner in = new Scanner(System.in);int n=in.nextInt();boolean[] isprime = new boolean[n+1];for ( int i=0; i<isprime.length; ++i ){isprime[i]=true;}for (int i=2; i<isprime.length; ++i ){if ( isprime[i] ){for ( int k=2; i*k<isprime.length; ++k ){isprime[k*i]=false;}}}for ( int i=2; i<isprime.length; ++i ){if ( isprime[i] ){System.out.print(i+" ");}}}}