Question

如何使用linkedList类中的方法以相反的顺序打印我的链表数组：

for (int j = 0; j < FutureValueLinkedList.size(); j++)
     {

        String myArrayLinkedList = FutureValueLinkedList.get(j);
        System.out.println(myArrayLinkedList + "\t"); 
     }
    System.out.println();

addLast（）能够做到吗？

import java.util.*;
import java.text.*;

public class FutureValueApp
 {
public static void main(String[] args)
{
    LinkedList<String> FutureValueLinkedList = new LinkedList<>();
    // display a welcome message
    System.out.println("Welcome to the Future Value Calculator");
    System.out.println();

    // perform 1 or more calculations
    Scanner sc = new Scanner(System.in);
    String choice = "y";
    while (choice.equalsIgnoreCase("y"))
    {

        // get the input from the user
        System.out.println("DATA ENTRY");
        double monthlyInvestment = getDoubleWithinRange(sc,
            "Enter monthly investment: ", 0, 1000);
        double interestRate = getDoubleWithinRange(sc,
            "Enter yearly interest rate: ", 0, 30);
        int years = getIntWithinRange(sc,
            "Enter number of years: ", 0, 100);

        // calculate the future value
        double monthlyInterestRate = interestRate/12/100;
        int months = years * 12;
        double futureValue = calculateFutureValue(
            monthlyInvestment, monthlyInterestRate, months);

        // get the currency and percent formatters
        NumberFormat currency = NumberFormat.getCurrencyInstance();
        NumberFormat percent = NumberFormat.getPercentInstance();
        percent.setMinimumFractionDigits(1);

        // format the result as a single string
        String results =
              "Monthly investment:\t"
                  + currency.format(monthlyInvestment) + "\n"
            + "Yearly interest rate:\t"
                  + percent.format(interestRate/100) + "\n"
            + "Number of years:\t"
                  +  years + "\n"
            + "Future value:\t\t"
                  + currency.format(futureValue) + "\n";

        // print the results
        System.out.println();
        System.out.println("FORMATTED RESULTS");
        System.out.println(results);

      String monthlyInvestmentFormat = currency.format(monthlyInvestment);
      String interestRateFormat = percent.format(interestRate/100);
      String futureValueFormat = currency.format(futureValue);

      FutureValueLinkedList.add(monthlyInvestmentFormat + "\t" + 
      interestRateFormat +  "\t" + Integer.toString(years) +
              "\t" + futureValueFormat);




        // see if the user wants to continue
        System.out.print("Continue? (y/n): ");
        choice = sc.next();
        System.out.println();
    }

     System.out.println("Future Value Calculations ");
     System.out.println();
     System.out.print("Inv/Mo.\tRate\tYears\tFuture Value\n");
     for (int j = 0; j < FutureValueLinkedList.size(); j++)
     {

        String myArrayLinkedList = FutureValueLinkedList.get(j);
        System.out.println(myArrayLinkedList + "\t"); 
     }
    System.out.println();
}

Answer 1

如果您只想输出反转列表，可以使用descendingIterator作为Ostap建议。但是，如果你想在某处存储反向列表，那么你可以这样做：

LinkedList<String> reversedFutureValueLinkedList = Collections.reverse(FutureValueLinkedList );

Answer 2

查看LinkedList#descendingIterator()

LinkedList<Integer> l = new LinkedList<Integer>();
l.add(1);
l.add(2);
l.add(3);

Iterator i = l.descendingIterator();
while(i.hasNext()) {
    System.out.print(i.next() + " ");
}

打印出来：

3 2 1

如何从Linked List类实现一个方法来反转我的linkedList？

2 个答案: