1013 数素数 (20 分) Java练习&PTA乙级

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筛法打个包含1e4+的素数表，直接遍历输出，控制格式

import java.lang.reflect.Array;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;
import java.util.Vector;

import javax.swing.plaf.basic.BasicInternalFrameTitlePane.MaximizeAction;

public class Main {
	public static int maxn = 110000 + 7;
	public static boolean[] f = new boolean[maxn];
	public static Vector<Integer> prim = new Vector();
	public static void init() {
		for(int i = 2; i < maxn; ++i) {
			f[i] = true;
		}
		for(int i = 2; i < maxn; ++i) {
			if(f[i]) {
				prim.add(i);
				for(int j = i+i; j < maxn; j += i) {
					f[j] = false;
				}
			}
		}
		//System.out.println(prim.size());
	}
	public static void main(String[] args) {
		init();
		Scanner in = new Scanner(System.in);
		int a = in.nextInt(), b = in.nextInt();
		boolean fa = false;
		for(int i = a-1; i < b; ++i) {
			if(fa) System.out.print(" ");
			else fa = true;
			System.out.print(prim.get(i));
			if((i-a+2) % 10 == 0) {
				System.out.println();
				fa = false;
			}
		}
	}
	
}