110 圖形面積

import java.util.Scanner;
public class JPA110 {

    public static void main(String args[]) {
   
        double totalarea;
        System.out.printf("圓形面積為：%f \n",calCircle(5));
        System.out.printf("三角形面積為：%f \n",calTriangle(10,5));
        System.out.printf("方形面積為：%f \n",calRectangle(5,10));
        totalarea = calCircle(5)+calTriangle(10,5)+calRectangle(5,10);
        System.out.printf("此圖形面積為：%f \n",totalarea);
    }
    static double calCircle(double r) {
        return r*r*Math.PI;
    }
   
    static double calTriangle(double x,double y) {
        return x*y;
    }
   
    static double calRectangle(double x,double y) {
        return x*y/2;
    }
}


109 變數範圍

public class JPA109 {

    public static int adder (int s, int a, int e) {
        return s+a+e;
    }

    public static int gameRating (int s, int a, int e) {
        return adder(s,a,e);
    }

    public static void main (String argv[]) {
        int skill = 6, action = 9, excitment = 8, result;
        result = gameRating(skill, action, excitment);
        System.out.print("The rating of the game is ");
        System.out.println(result);
    }
}

108 覆載方法

class JPA108 {

  public static int add(int i,int j){
  System.out.println("Adding two integers : "+i+","+j);
  return i+j;
  }
 
  public static double add(double i,double j){
  System.out.println("Adding two doubles : "+i+","+j);
  return i+j;
  }
 
  public static String add(String i,String j){
  System.out.println("Adding two strings : "+i+","+j);
  return i+j;
  }

  public static void main (String[] args) {
    int i = add(2, 3);
    double d = add(5.2, 4.3);
    String s = add("I love ", "Java!!");
    System.out.printf("%d %f %s %n", i, d, s);
  }
 
}

107 運動成績

public class JPA107 {
    public static void main(String argv[]) {
        int action = 1, skill = 2, teamgame = 3;

Basketball Basketball = new Basketball();
Baseball Baseball = new Baseball();

        System.out.println("The basketball grade is " + Basketball.calGrade(action,skill,teamgame));
        System.out.println("The baseball grade is " + Baseball.calGrade(skill,teamgame));
    }
}


class Basketball {
    int calGrade(int a,int s,int t){
        return a + s + t;
    }
}


class Baseball {
    int calGrade(int s,int t){
        return 10 + s + t;
    }
}

106 數學函數

public class JPA106 {

    public static void main(String []argv){

System.out.printf("f(-3.2)=%.4f\n",f(-3.2));

System.out.printf("f(-2.1)=%.4f\n",f(-2.1));

System.out.printf("f(0)=%.4f\n",f(0));

System.out.printf("f(2.1)=%.4f\n",f(2.1));

    }

    public static double f(double x){

    return 3*(x*x*x)+2*x-1;

    }

}

105 存錢筒

import java.util.*;
public class JPA105 {
    public static void main(String [] args){
String name;
int one;
int five;
int ten;
int fifty;
Scanner sc=new Scanner(System.in);
System.out.print("請輸入您的姓名 :");
name = sc.next();
System.out.println("Hi,"+name+",請輸入您的銅板個數:");
System.out.print("請輸入1元的數量:");
one=sc.nextInt();
System.out.print("請輸入5元的數量:");
five=sc.nextInt();
System.out.print("請輸入10元的數量:");
ten=sc.nextInt();
System.out.print("請輸入50元的數量:");
fifty=sc.nextInt();
int total=one*1+five*5+ten*10+fifty*50;
System.out.print("您的錢總共有:"+(total/1000)+" 千 "+(total/100-(total/1000)*10)+" 百 "+((total%100-(total%10)*10)/10)+" 十 "+(total%10)+" 元");

    }
}

104 距離計算

import java.util.*;
public class JPA104{
public static void main(String [] argvs){
double x1,y1,y2,x2;
Scanner sc = new Scanner(System.in);
System.out.print("輸入第1題的x座標和y座標:");
x1=sc.nextDouble();
y1=sc.nextDouble();
System.out.print("輸入第2題的x座標和y座標:");
x2=sc.nextDouble();
y2=sc.nextDouble();
System.out.printf("介於<%.2f,%.2f>和<%.2f,%.2f>之間的距離是%.2f",x1,y1,x2,y2,Math.sqrt(Math.pow((x2-x1),2)+Math.pow((y2-y1),2)));
}
}

103 計算平均值

import java.util.Scanner;
public class JPA103 {
public static void main (String [] argvs){
  Scanner sc= new Scanner(System.in);
  double total=0;
  System.out.println("Please input:");
  for(int i = 0;i<3;i++){
  total+=sc.nextDouble();
  }
System.out.printf("Average: %.2f",total/3);
}
}

102 單位換算

import java.util.Scanner;
public class JPA102 {

public static void main (String [] args){

double kg;
Scanner sc=new Scanner(System.in);
System.out.println("Please input:");
kg = sc.nextDouble();
System.out.printf("%f kg = %f ponds",kg,kg*2.20462);
}
}

101 字串處理

其中一個錯誤在編碼格式→→"由UTF-8 改成ANSI"

public class JPA101 {
    public static void main (String args[]) {
        System.out.println("I love Java!");
        System.out.println("Java is so good！");
    }
}