JAVA上机小程序

JAVA上机作业（9.10-11.5） 1. 1-1/3+1/5-1/7···的前10000项的运算结果 方法一： public class Sum { static int END = 10000; public static void main(String args[]) { double sum = 0.0; for (double i = 0.0; i < END; i++) { if (i % 2 == 0) { sum += 1/(2*i + 1); } else { sum -= 1/(2*i + 1); } } System.out.println(sum); } } 方法二： class Example { public static void main (String args[]) { double x=1,y=1,z=1,sum=0; int i=1; for(i=1;i<=10000;i++) { z=x/y; sum=sum+z; x=-x; y=y+2; } System.out.println(sum); } } 2. 猜数 方法一： import java.util.*; public class Number { public static void main(String args[]) { Scanner reader=new Scanner(System.in); int m=(int)(Math.random()*100)+1; int n=reader.nextInt(); int min=1,max=100; while(n!=m) { if(n>m) { max=n; System.out.println("范围在"+min+"和"+max+"之间"); } if(n{ min=n; System.out.println("范围在"+min+"和"+max+"之间"); } n=reader.nextInt(); } System.out.println("恭喜你，猜对了"); } } 方法二： import java.util.*; class Example { public static void main(String args[]) { int realNumber,yourGuess,max,min; realNumber=(int)(Math.random()*100)+1; min=1; max=100; Scanner reader=new Scanner(System.in); yourGuess=reader.nextInt(); while(true) { if(yourGuess==realNumber) { System.out.println("猜对了"); break; } else if(yourGuess>realNumber&&yourGuess{ max=yourGuess; } else if(yourGuessmin) { min=yourGuess; } System.out.println(min+"-"+max); yourGuess=reader.nextInt(); } } } 3. 构造分数 public class fs { private int fz; private int fm; public fs() { } public fs(int fz,int fm) { this.fz=fz; this.fm=fm; } public int getfz() { return fz; } public void setfz(int fz) { this.fz= fz; } public int getfm() { return fm; } public void setfm(int fm) { this.fm = fm; } public String toString() { return fz+"/"+fm; } public fs add(fs x) { int fz=this.getfz()*x.fm+x.getfz()*this.fm; int fm=this.getfm()*x.getfm(); return new fs(fz,fm); } public fs sub(fs x) { int fz=this.getfz()*x.fm-x.getfz()*this.fm; int fm=this.getfz()*x.getfm(); return new fs(fz,fm); } } class Example { public static void main (String[] args) { fs fs_a=new fs(1,3); fs fs_b=new fs(1,2); System.out.println(fs_a.add(fs_b)); System.out.println(fs_a.sub(fs_b)); } } 4. 求体积 正方体 class cube { double x; cube(double a) { x=a; } double getvolume() { return x*x*x; } } public class example { public static void main(String args[]) { cube one=new cube(10); double volume; volume=one.getvolume(); System.out.println(volume); } } 立方体 class cube { double x,y,z; cube(double a,double b,double c) { x=a; y=b; z=c; } double getvolume() { return x*y*z; } } public class example { public static void main(String args[]) { cube one=new cube(10,12,14); double volume; volume=one.getvolume(); System.out.println(volume); } } 5. 设计一个平面坐标系中的点MyPoint类，它仅包含两个属性：横坐标和纵坐标，以及构造方法和移动坐标、返回坐标的方法,重写toString()返回点的横纵坐标。使用MyPoint类派生出圆MyCircle类，继承的点类描述圆的圆心，MyCircle类还用包括半径作为属性，有参和无参构造方法，设置半径和修改半径，计算面积和周长等方法，重写toString()返回点的横纵坐标和半径的字符串形式，并编写主程序演示该类的用法。 public class MyPoint { private double x,y; public MyPoint() { } public MyPoint(double a,double b) { x=a; y=b; } void setx(double a) { x=a; } void sety(double b) { y=b; } double getx() { return x; } double gety() { return y; } public String toString() { return x+","+y; } } class example1 { public static void main(String []args) { MyPoint one=new MyPoint(10,5); System.out.println(one.toString()); } } public class Circle extends MyPoint { protected double r; public Circle( ) { super( ); } public Circle ( double r ) { super(); this.r=r; }