越努力，越幸运！

package com.webmagic;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import us.codecraft.webmagic.Page;
import us.codecraft.webmagic.Site;
import us.codecraft.webmagic.Spider;
import us.codecraft.webmagic.processor.PageProcessor;
import us.codecraft.webmagic.selector.Selectable;

import java.io.File;
import java.io.FileOutputStream;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.stream.IntStream;

import static java.util.stream.Collectors.toList;

public class W3PdfProcessor implements PageProcessor {
    public static final String D_DEV_SOUP_SRC_MAIN_RESOURCES_W3_PDF = "D:\\dev\\soup\\src\\main\\resources\\w3Pdf\\";
    private Site site = Site.me().setRetryTimes(3).setSleepTime(1000);

    static Pdf pdf = new Pdf("上****娃）",316,"******/4ff5fff9005d59bbf09fd0/"
            ,"******************");


    @Override
    public void process(Page page) {
        byte[] bytes = page.getBytes();
        Selectable url = page.getUrl();
        List<String> strings = Arrays.asList(url.get().split("/"));
        Collections.reverse(strings);
        try {
            saveFile(pdf.getName()+"\\"+strings.get(0)+"."+pdf.getName()+".png",bytes);
        } catch (Exception e) {
            e.printStackTrace();
        }


    }

    @Override
    public Site getSite() {
        return site;
    }

    public static void main(String[] args) {
        new File(D_DEV_SOUP_SRC_MAIN_RESOURCES_W3_PDF+pdf.getName()).mkdir();
        List<String> collect = IntStream.rangeClosed(1, pdf.getPage())
                .mapToObj(e -> pdf.getPreUrl() + e).collect(toList());
        Spider
                .create(new W3PdfProcessor())
                .addUrl(collect.toArray(new String[0]))
                .thread(10)
                .run();
    }

    /**
     * 将字节流转换成文件
     * @param filename
     * @param data
     * @throws Exception
     */
    public static void saveFile(String filename,byte [] data)throws Exception{
        if(data != null){
            String filepath = D_DEV_SOUP_SRC_MAIN_RESOURCES_W3_PDF + filename;
            File file = new File(filepath);
            if(file.exists()){
                file.delete();
            }
            FileOutputStream fos = new FileOutputStream(file);
            fos.write(data,0,data.length);
            fos.flush();
            fos.close();
        }
    }
}
@Data
@AllArgsConstructor
@NoArgsConstructor
class Pdf{
    String name;
    int page;
    String preUrl;
    String pdfOnlineUrl;
}

import java.math.BigInteger;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;
import java.util.Scanner;
import java.util.function.BiFunction;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.stream.IntStream;
import java.util.stream.Stream;

/**
 */
public class Main {
    public static boolean isZhishu(int n){
        int sqrt = (int)Math.sqrt((double) n);
        return IntStream.rangeClosed(2, sqrt).noneMatch(i -> n % i == 0);
    }
    private static Function<String,BigInteger> bigInteger = BigInteger::new;


    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while(in.hasNext()){
            int x=in.nextInt();
            System.out.println(gongbeishu(x));
        }
    }
    static BiFunction<BigInteger,BigInteger,BigInteger> multiply2_a=
            (e, n)-> Stream.generate(()->e).limit(n.longValue()).reduce(bigInteger.apply("1"), getBigIntegerBinaryOperator());

    private static BinaryOperator<BigInteger> getBigIntegerBinaryOperator() {
        return (a, b)->bigInteger.apply(a.toString()).multiply(bigInteger.apply(b.toString()));
    }

    public static BigInteger gongbeishu(int n){
        Map<Integer, Integer> objectObjectConcurrentHashMap = new HashMap<>();
        IntStream.rangeClosed(2, n). forEach(
            fang->{
                IntStream.rangeClosed(2, n).filter(Main::isZhishu)
                        .filter(
                                e->multiply2_a.apply(bigInteger.apply(e+""),bigInteger.apply(fang+"")).compareTo(bigInteger.apply(n+""))==-1
                        )
                        .forEach(a->{
                            objectObjectConcurrentHashMap.put(a,fang);
                        })
                ;
            }
        );
        return IntStream.rangeClosed(2, n).filter(Main::isZhishu).mapToObj(e->{
            return multiply2_a.apply(bigInteger.apply(e+""),bigInteger.apply(Optional.ofNullable(objectObjectConcurrentHashMap.get(e)).orElse(1)+""));
        })
                .reduce(bigInteger.apply("1"), getBigIntegerBinaryOperator());

    }
}