Question

我在计算机科学课程的编程工作中遇到了麻烦。该计划是添加罗马数字。我不知道如何开始实际添加罗马数字的代码并输出两个数字的总和：这是我到目前为止主程序的代码：

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

/**
 * Class RomanNumeralCalculator - write a description of the class here
 * 
 * @author (your name) 
 * @version (a version number)
*/
public class RomanNumeralCalculator extends JFrame
{
   public static JPanel panel1, panel2, panel3, panel4;
   public static JLabel main1, main2, label1, label2,label3,label4,image;
   public static JTextField number1, number2;
   public static JTextArea output;
   public static JButton calculate,exit;
   public static String input="Enter"; 
   public static int position;
String num="";
public RomanNumeralCalculator()
{
    super ("Roman Numeral Calculator");
    setSize(1045,740);
    setLocation(0,0);
    Container container = getContentPane();
    container.setBackground(Color.GREEN);

    JLabel image=new JLabel(new ImageIcon("romanNumerals.jpg"));

    panel1=new JPanel();
    panel2=new JPanel();
    panel3=new JPanel();
    panel4=new JPanel();

    panel1.setLayout(new GridLayout(2,7));
    panel1.setBackground(Color.GREEN);
    panel2.setLayout(new FlowLayout());
    panel2.setBackground(Color.MAGENTA);
    panel3.setLayout(new FlowLayout());
    panel3.setBackground(Color.YELLOW);
    panel4.setLayout(new FlowLayout());
    panel4.setBackground(Color.GRAY);

    JLabel main1=new JLabel("Welcome To The Roman Numerals Calculator");
    JLabel main2=new JLabel("BY: Harpreet Singh, Date: 31/10/2013");

    label3=new JLabel("Here are the following numbers that can be used in the calculator:");
    label4=new JLabel("I=1 , V=5 , X=10 , L=50 , C=100 , D=500 , M=1000");

    calculate=new JButton("Calculate");
    exit=new JButton("Exit");

    ButtonHandler handler = new ButtonHandler();
    calculate.addActionListener(handler);
    exit.addActionListener(handler);

    label1=new JLabel("Enter first number in roman numerals:");
    number1=new JTextField("",10);
    label2=new JLabel("Enter second number in roman numerals:");
    number2=new JTextField("",10);

    output=new JTextArea(10,100);
    output.setEditable(false);

    container.setLayout(new BorderLayout());
    container.add(panel1, BorderLayout.NORTH);
    container.add(panel2, BorderLayout.CENTER);
    container.add(panel3, BorderLayout.SOUTH);

    panel1.add(main1);
    panel1.add(main2);
    panel1.add(image);
    panel2.add(label3);
    panel2.add(label4);
    panel3.add(label1);
    panel3.add(number1);
    panel3.add(label2);
    panel3.add(number2);
    panel3.add(calculate);        
    panel3.add(exit);

    setVisible(true);
}

public class ButtonHandler implements ActionListener
{
    public void actionPerformed(ActionEvent e)
    {
        if (e.getSource()==calculate)
        {
            String num1=number1.getText();
            String num2=number2.getText();
            CalculateNumbers x=new CalculateNumbers();
            x.calculations(num1,num2);
        }
        else if (e.getSource()==exit)
        {
            System.exit(0);
        }
    }
}

public static void main (String args[])
{
    /*String choice=JOptionPane.showInputDialog(null, "Please Type In 'Enter' to Continue: ", "Enter", JOptionPane.PLAIN_MESSAGE);
    if ((choice == null) || ((choice != null) && !(choice.equalsIgnoreCase(input))))
    {
    JOptionPane.showMessageDialog(null, "Invalid Password. Please Try Again.");
    System.exit(0);
    }*/
    //else
    //{
    //JOptionPane.showMessageDialog(null, "Correct Password");
    RomanNumeralCalculator application = new RomanNumeralCalculator();
    //}
}

}

Answer 1

首先写两个方法

将罗马数字转换为常规数字
将常规号码转换为罗马数字

当用户提供罗马数字输入时，将它们转换为常规数字执行算术运算，最后将结果转换为罗马数字

同时检查Converting Roman Numerals To Decimal和Convert Int to Roman Numeral

Answer 2

创建一个罗马数字类，它将转换您给出十进制数的数字，反之亦然。如果你愿意，你甚至可以让它静止。

这将使您的代码看起来更好，更面向对象。

这里有一个算法解释。

roman number algorithm

Answer 3

       import java.util.Scanner;

        public class Roman {

        public static void main(String[] args) {

        Scanner stdIn = new Scanner(System.in);

         System.out.print("Enter a Roman Number:> ");

          char[] roman = stdIn.nextLine().toCharArray();

    int total = 0;
    for(int i = roman.length-1; i > -1; i--){
        switch(roman[i]){
            case 'I':
                total += value(roman[i]); break;
            case 'V':
            case 'X':
            case 'L':
            case 'C':
            case 'D':
            case 'M':
                if(i != 0 && (value(roman[i-1]) < value(roman[i]))){
                    total += value(roman[i]) - value(roman[i-1]);
                    i--;
                }else{
                    total += value(roman[i]);
                }
                break;
        }
    }
    System.out.println(total);
}

public static int value(char c){
    switch(c){
        case 'I':
            return 1;
        case 'V':
            return 5;
        case 'X':
            return 10;
        case 'L':
            return 50;
        case 'C':
            return 100;
        case 'D':
            return 500;
        case 'M':
            return 1000;
        default:
            return 0;
    }
} }

如何在java中添加罗马数字

3 个答案: