//1.3.20

    /**

     * delete the kth element in a linked list, if it exists.

     *

     * @param k the kth element, it should larger than 1

     * @throws IllegalArgumentException if k < 1

     * @throws NoSuchElementException if the size of the list is less than k

     */

    public Item delete(int k) {

        if(k < 1)

            throw new IllegalArgumentException("k must larger than 1");

        Node<Item> precurrent = new Node<Item>();

        precurrent.next = first;

        Item item;

        while(precurrent.next != null && k > 1) {

            precurrent = precurrent.next;

            k--;

        }

        if(precurrent.next == null)

            throw new NoSuchElementException("LinkedList hasn't so many elements");

        item = precurrent.next.item;

        if(precurrent.next == first)

            first = precurrent.next.next;

        else

            precurrent.next = precurrent.next.next;

        return item;

    }

package com.qiusongde.linkedlist;

import edu.princeton.cs.algs4.StdIn;

import edu.princeton.cs.algs4.StdOut;

public class Exercise1320 {

    public static void main(String[] args) {

        LinkedList<String> list = new LinkedList<String>();

        while(!StdIn.isEmpty()) {

            String s = StdIn.readString();

            list.insertAtBeginning(s);

            StdOut.println("insertAtBeginning success: " + s);

            StdOut.println(list);

        }

        int k = 5;

        String s = list.delete(k);

        StdOut.println("delete " + k + "th Element success: "+ s);

        StdOut.println(list);

        for(int i = 0; i < 4; i++) {

            k = 1;

            s = list.delete(k);

            StdOut.println("delete " + k + "th Element success: "+ s);

            StdOut.println(list);

        }

        k = 5;

        s = list.delete(k);

        StdOut.println("delete " + k + "th Element success: "+ s);

        StdOut.println(list);

    }

}

to

be

or

not

to

insertAtBeginning success: to

to

insertAtBeginning success: be

be to

insertAtBeginning success: or

or be to

insertAtBeginning success: not

not or be to

insertAtBeginning success: to

to not or be to

delete 5th Element success: to

to not or be

delete 1th Element success: to

not or be

delete 1th Element success: not

or be

delete 1th Element success: or

be

delete 1th Element success: be

Exception in thread "main" java.util.NoSuchElementException: LinkedList hasn't so many elements

    at com.qiusongde.linkedlist.LinkedList.delete(LinkedList.java:130)

    at com.qiusongde.linkedlist.Exercise1320.main(Exercise1320.java:32)