Javau有多少v高uyed

package step1;


import java.lang.Math;
import java.util.Scanner;


public class Triangle {
	double a,b,c;
	
	public Triangle(double a, double b, double c) {
		this.a = a;
		this.b = b;
		this.c = c;
	}

	public double getArea() {
		double s = (a + b + c) / 2;
		return Math.sqrt(s * (s - a) * (s - b) * (s - c));
	}

	public double getPerimeter() {
		return a + b + c;
	}

	public static void main(String[] args) {
		Scanner input =new Scanner(System.in);
		double a = input.nextDouble();
		double b = input.nextDouble();
		double c = input.nextDouble();
    	Triangle t1 = new Triangle(a, b, c);
    	System.out.printf("三角形(%.1f,%.1f,%.1f)的面积为:%.2f\n",t1.a,t1.b,t1.c,t1.getArea());
    	System.out.printf("三角形(%.1f,%.1f,%.1f)的周长为:%.2f",t1.a,t1.b,t1.c,t1.getPerimeter());
	}

}

package step2;

import java.lang.Math;
 
public class Ring {
    double innerRadius, outerRadius;
    String color;
 
    public Ring(double innerRadius, double outerRadius, String color) {
        this.innerRadius = innerRadius;
        this.outerRadius = outerRadius;
        this.color = color;
    }
 
    public double getArea() {
        return Math.PI * (outerRadius * outerRadius - innerRadius * innerRadius);
    }
 
    public double getInnerPerimeter() {
        return 2 * Math.PI * innerRadius;
    }
 
    public double getOuterPerimeter() {
        return 2 * Math.PI * outerRadius;
    }
    
    public void setInnerRadius(double innerRadius){
    	this.innerRadius = innerRadius;
    }
    
    public void setOuterRadius(double outerRadius){
    	this.outerRadius = outerRadius;
    }
    
    public void setColor(String color){
    	this.color = color;
    }
    
 
    public static void main(String[] args) {
    	Ring ring = new Ring(5, 8, "red");
        System.out.printf("圆环的内半径: %.1f\n",ring.innerRadius);
        System.out.printf("圆环的外半径: %.1f\n",ring.outerRadius);
        System.out.println("圆环的颜色: "+ring.color);
        System.out.printf("圆环的面积: %.2f\n",ring.getArea());
        System.out.printf("圆环的外圆周长: %.2f\n",ring.getOuterPerimeter());
        System.out.printf("圆环的内圆周长: %.2f\n",ring.getInnerPerimeter());
        System.out.println();
        ring.setInnerRadius(4);
		ring.setOuterRadius(6);
		ring.setColor("blue");
		System.out.printf("圆环的内半径: %.1f\n",ring.innerRadius);
        System.out.printf("圆环的外半径: %.1f\n",ring.outerRadius);
        System.out.println("圆环的颜色: "+ring.color);
        System.out.printf("圆环的面积: %.2f\n",ring.getArea());
        System.out.printf("圆环的外圆周长: %.2f\n",ring.getOuterPerimeter());
        System.out.printf("圆环的内圆周长: %.2f",ring.getInnerPerimeter());
		
        
 
    }
}

package step3;


 
public class Student {
	int id;
	int age;
	String name;
 
	public Student(int id, int age, String name) {
		this.id = id;
		this.age = age;
		this.name = name;
	}
 
	public void increaseAge() {
		this.age += 1;
	}
 
	public static void main(String[] args) {
		// 创建并初始化学生数组
		Student s1 = new Student(1, 18, "小明");
		Student s2 = new Student(2, 20, "小张");
		Student s3 = new Student(3, 19, "小李");
		Student s4 = new Student(4, 18, "小王");
		Student s5 = new Student(5, 20, "小赵");
 
		Student s[] = { s1, s2, s3, s4, s5 }; // 给对象数组赋值
		System.out.println("班级学生名单如下：");
 
		// 显示所有学生信息
		for (Student student : s) {
			System.out.println("学号:" + student.id + ",姓名:" + student.name + ",年龄:" + student.age);
		}
 
		// 将所有学生年龄增加1岁
		System.out.println("所有学生年龄加 1 后...");
		for (Student student : s) {
			student.increaseAge();
		}
		for (Student student : s) {
			System.out.println("学号:" + student.id + ",姓名:" + student.name + ",年龄:" + student.age);
		}
 
		// 显示所有年龄大于20岁的学生信息
		int number = 0;
		for (Student student : s) {
			if (student.age > 20) {
				number++;
			}
		}
		System.out.println("大于 20 岁人数是：" + number);
	}
}