求质数…

import java.text.DecimalFormat;
import java.util.*;

public class Lab12Extended {
    static int MAX;
    public static void main(String args[]) {
        // This main method needs additions for the 100 point version.
        System.out.println("nThe "Sieve of Eratosthenes"n");
        Scanner input = new Scanner(System.in);
        System.out.print("Enter the primes upper bound ===> ");
        MAX=input.nextInt();
        boolean primes[];
        primes = new boolean[MAX+1];
        Arrays.fill(primes, true);
        primes[1]=false;
        computePrimes(primes);
        displayPrimes(primes);
    }

    public static void computePrimes(boolean primes[]) {
        int count;
        int test;
        int temp;
        System.out.println("nComputing Prime Number n");
         for (count=2;count<=MAX;count++){
             for (test=2;test<=MAX;test++){
                 if (count!=test){
                     temp=count%test;
                     if (temp==0){
                         primes[count]=false;
                     }
                 }
             }
         }
    }

    public static void displayPrimes(boolean primes[]) {
        System.out.println("Primes between 1 and "+MAX+"n");
        int count;
            DecimalFormat df = new DecimalFormat("000");
            for (count=2;count<=MAX;count++){
                if (primes[count]==true){
                    System.out.print(df.format(count)+" ");
                }
            }
    }
}

Animation_Sieve_of_Eratosth-2

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Microsoft Office Lab 2019

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Lab 9`

import java.applet.*;
import java.awt.*;

public class Lab9 extends Applet{

public void paint(Graphics g) {
resize(350, 250);
car body = new car(g);

}

}

class car extends shell{

public car(Graphics g){
super(g);
component com = new component(g);

}

}

class shell {

public shell(Graphics g){
g.setColor(Color.blue);
Polygon shell = new Polygon();
shell.addPoint(20, 200);//left top
shell.addPoint(20, 230);//left bottom
shell.addPoint(330, 230);//right bottom
shell.addPoint(330, 200);//right top
shell.addPoint(270, 200);//right corner
shell.addPoint(250, 150);//top right
shell.addPoint(130, 150);//top left
shell.addPoint(90, 200);//left corner
g.fillPolygon(shell);
}

}

class component {

public component(Graphics g){
wheels(g,35,215);
wheels(g,285,215);
door(g);
windows(g);

}

public void wheels(Graphics g,int x,int y){
g.setColor(Color.black);
g.fillOval(x, y, 30, 30);

}

private void door(Graphics g) {
Polygon door1 = new Polygon();
door1.addPoint(130, 155);//left top
door1.addPoint(95, 200);//left middle
door1.addPoint(95,225);//left bottom
door1.addPoint(175,225);//right bottom
door1.addPoint(175,155);//right top
g.drawPolygon(door1);

Polygon door2 = new Polygon();
door2.addPoint(180,155);//left top
door2.addPoint(180, 225);//left bottom
door2.addPoint(265, 225);//right bottom
door2.addPoint(265, 200);//right middle
door2.addPoint(245, 155);//right top
g.drawPolygon(door2);

}
private void windows(Graphics g) {
g.setColor(Color.white);

Polygon window1 = new Polygon();
window1.addPoint(131, 156);//left top
window1.addPoint(96, 200);//left bottom
window1.addPoint(175, 200);//right bottom
window1.addPoint(175, 156);//right top
g.fillPolygon(window1);

Polygon window2 = new Polygon();
window2.addPoint(181, 156);//left top
window2.addPoint(181, 200);//left bottom
window2.addPoint(265, 200);//right bottom
window2.addPoint(245, 156);//right top
g.fillPolygon(window2);

}
}

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