package mp;

import java.text.DecimalFormat;
import javax.swing.JOptionPane;

public class Exec {
        public static void main(String[] args) {
                double amount = Double.parseDouble(JOptionPane.showInputDialog("请输入金额"));
                if (amount < 0)
                        amount = 0;
                DecimalFormat nf = new DecimalFormat("#,##0.0000");
                System.out.println(nf.format(amount));          
        }
}