java第一周的实验题，待优化（李老师）

package homework;

public class SumNum {

	public static void main(String[] args) {
	
		int sumFactorial = 0;
		final int NUMBER = 10;//一共十个数字
		/*
		 * 累加阶乘
		 * */
		for(int i = 1;i<=NUMBER;i++) {
			sumFactorial += factorial(i);
		}
		System.out.println(sumFactorial);

	}
	
	/*
	 * 计算数字的阶乘
	 * */	
	public static int factorial(int num) {
		int sum = 1;
		for(int i=1; i<=num; i++) {
			sum *= i;
		}
		return sum;
	}

}

第二题

package homework;

public class Circle {
	final static double PI = 3.14;//常量PI
	double r; //圆的半径
	double area; //圆的面积
	double perimeter;//圆的周长
	
	public Circle() {
		this.r = 0;
	}
	
	public Circle(double r) {
		this.r = r;
	}
	
	/*
	 * 返回面积
	 * */
	public double getArea() {
		this.area = PI * this.r * this.r;
		return this.area;
	}
	/*
	 * 返回周长
	 * */
	public double getPerimeter() { 
		this.perimeter = 2 * PI * r;
		return this.perimeter;
	}
	
	/*
	 * 输出信息
	 * */
	public void show() {
		System.out.println("圆的半径=" + r);
		System.out.println("圆的周长=" + getPerimeter());
		System.out.println("圆的面积=" + getArea());
	}
	
	/*
	 * Test
	 * */
	public static void main(String[] args) {
		Circle myCircle = new Circle(3);
		myCircle.show();
		
	}
}

第三题

package homework;

public class Student {
	String  sNO; //学号
	String sName;	//姓名
	String sSex;	//性别
	double sJava;	//成绩
	
	public Student(String XH, String XM, String XB, double CJ) {
		this.sNO = XH;
		this.sName = XM;
		this.sSex = XB;
		this.sJava = CJ;
	}
	
	/*
	 * 返回学号
	 * */
	public String getNo() {
		
		return("学号: " + sNO + " ");
		
	}
	
	/*
	 * 返回姓名
	 * */
	public String getName() {
		
		return("姓名: " + sName +" ");
		
	}
	
	/*
	 * 返回性别
	 * */
	public String getSex() {
		
		return("性别: " + sSex +" ");
		
	}
	
	/*
	 * 返回成绩
	 * */
	public String getJava() {
		
		return("成绩: " + sJava +" ");
		
	}
	
	public static void main(String[] args) {
		
		Student liuLuFei = new Student("001","刘璐菲","男",99);
		Student liJianYe = new Student("002","李建业","女",20);
		Student liSan = new Student("003","李三","男",100);
		Student liXiaoYe = new Student("004","李小业","女",10);
		Student liErYe = new Student("005","李二业","男",18);
		Student class1[]= {liuLuFei, liJianYe, liSan, liXiaoYe, liErYe};
		
		/*
		 * 输出5为学生的信息
		 * */
		for(int i=0; i< class1.length;i++) {
			System.out.println(class1[i].getNo()+class1[i].getName()+class1[i].getSex()+class1[i].getJava());
		}
		
		/*
		 * 计算5位学生的平均成绩
		 * */
		double sum = 0, ave = 0;
		for(int i=0;i< class1.length;i++) {
			sum += (double)class1[i].sJava;
		}
		ave = sum / class1.length;
		System.out.println("平均成绩: " + ave);
		
		/*
		 * 计算5为学生成绩的最大最小值
		 * */
		double maxJava = 0, minJava = 100;
		for(int i =0;i<class1.length;i++) {
			
			if(class1[i].sJava > maxJava) {
				maxJava = class1[i].sJava;
			}
			if(class1[i].sJava < minJava) {
				minJava = class1[i].sJava;
			}
		}
		System.out.println("最大成绩:" + maxJava);
		System.out.println("最小成绩:" + minJava);
		
	}
	
	
	
}