跟着我爹学Java 12-13天

12.1 查找给定元素所处的位置. 找不到就返回 -1.
12.2 在给定位置增加元素. 如果线性表已满, 或位置不在已有位置范围之内, 就拒绝增加. 该位置可以是在最后一个元素之后一个.
12.3 删除定定位置的元素. 要处理给定位置不合法的情况. 该位置必须是已经有数据的.
12.4 函数 要求同样的输入参数获得同样的输出结果, 但 方法 所依赖的数据既包括参数列表中给出的，也依赖于对象的成员变量. 因此, 面向对象所涉及的参数列表要短些. 例如, locate 方法就有效利用了 length 和 data 这两个成员变量.

package linear_data_structure;

public class SequentialList {
    public static final int MAX_LENGTH = 10;
    //The maximal length of the list.It is a constant.
    int length;

    int[] data;

    public SequentialList() {
        length = 0;
        data = new int[MAX_LENGTH];
    }

    public SequentialList(int[] paraArry) {
        data = new int[MAX_LENGTH];
        length = paraArry.length;

        for (int i = 0; i < paraArry.length; i++) {
            data[i] = paraArry[i];
        }
    }

    public String toString() {
        String resultString = "";
        if (length == 0) {
            return "empty";
        }

        for (int i = 0; i < length - 1; i++) {
            resultString += data[i] + ", ";
        }

        resultString += data[length - 1];
        return resultString;
    }

    public void reset() {
        length = 0;
    }

    //find the index of the given value . If it appears in mutiple positions,
    //simply return the first one.
    public int indexof(int paraValue) {
        int tempPosition = -1;

        for (int i = 0; i < length; i++) {
            if (data[i] == paraValue) {
                tempPosition = i;
                break;
            }
        }
        return tempPosition;
    }


    /*Insert a value to a position. If the list is already full,do nothing.
    @param paraPosition The given position.
    @param paraValue    the given value.
    @return Success or not.
   */
    public boolean insert(int paraPosition, int paraValue) {
        if (length == MAX_LENGTH) {
            System.out.println("List full.");
            return false;
        }

        if (paraPosition < 0 || paraPosition > length) {
            System.out.println("The position" + paraPosition + "is out of bounds");
            return false;
        }

        for (int i = length; i > paraPosition; i--) {
            data[i] = data[i - 1];

        }
        data[paraPosition] = paraValue;
        length++;
        return true;
    }

    //Delete a value at a position
    //@param paraPosition The given position.
    //@return Success or not.
    public boolean delete(int paraPosition) {
        if ((paraPosition < 0) || (paraPosition >= length)) {
            System.out.println("The position " + paraPosition + " is out of bounds");
            return false;
        }
        for (int i = paraPosition; i < length - 1; i++) {
            data[i] = data[i + 1];
        }
        length--;
        return true;
    }

    public static void main(String[] args) {
        int[] tempArray = {1, 4, 6, 9};
        SequentialList tempFirstList = new SequentialList(tempArray);
        System.out.println("Initialized,the list is: " + tempFirstList.toString());
        System.out.println("Again, the list is: " + tempFirstList);

        int tempValue = 4;
        int tempPosition = tempFirstList.indexof(tempValue);
        System.out.println("The position of " + tempValue + " is " + tempPosition);

        tempValue = 5;
        tempPosition = tempFirstList.indexof(tempValue);
        System.out.println("The position of " + tempValue + " is " + tempPosition);

        tempPosition = 2;
        tempValue = 5;
        tempFirstList.insert(tempPosition, tempValue);
        System.out.println(
                "After inserting " + tempValue + " to position " + tempPosition + ", the list is: " + tempFirstList);

        tempPosition = 2;
        tempValue = 5;
        tempFirstList.insert(tempPosition, tempValue);
        System.out.println(
                "After inserting " + tempValue + " to position " + tempPosition + ", the list is: " + tempFirstList);
        tempPosition = 3;
        tempFirstList.delete(tempPosition);
        System.out.println("After deleting data at position " + tempPosition + ", the list is: " + tempFirstList);

        for (int i = 0; i < 8; i++) {
            tempFirstList.insert(i, i);
            System.out.println("After inserting " + i + " to position " + i + ", the list is: " + tempFirstList);
        } // Of for i

        tempFirstList.reset();
        System.out.println("After reset, the list is: " + tempFirstList);
    }//Of main

}

学习了基础的查找，插入，删除操作，内容比较简单，不做过多说明，注意对列表的操作即可。

package linear_data_structure;

public class LinkedList {
    class Node {
        int data;
        Node next;

        public Node(int paraValue) {
            data = paraValue;
            next = null;
        }
    }

    Node header;

    public LinkedList() {
        header = new Node(0);
    }

    public String toString() {
        String resultString = "";
        if (header.next == null) {
            return "empty";
        }
        Node tempNode = header.next;
        while (tempNode.next != null) {
            resultString += tempNode.data + ", ";
            tempNode = tempNode.next;
        }
        resultString+=tempNode.data;
        return resultString;
    }

    public void reset() {
        header.next = null;
    }

    public int locate(int paraValue) {
        int tempPosition = -1;
        Node tempNode = header.next;
        int tempCurrentPosition = 0;
        while (tempNode != null) {
            if (tempNode.data == paraValue) {
                tempPosition = tempCurrentPosition;
                break;
            }
            tempNode = tempNode.next;
            tempCurrentPosition++;
        }
        return tempPosition;
    }

    public boolean insert(int paraPosition, int paraValue) {
        Node tempNode = header;
        Node tempNewNode;

        for (int i = 0; i < paraPosition; i++) {
            if (tempNode.next == null) {
                System.out.println("The position " + paraPosition + " is illeagal.");
                return false;
            }
            tempNode = tempNode.next;
        }
        //Construct a new node.
        tempNewNode = new Node(paraValue);
        //Link them
        tempNewNode.next = tempNode.next;
        tempNode.next = tempNewNode;

        return true;

    }

    public boolean delete(int paraPosition) {
        if (header.next == null) {
            System.out.println("Cannot delete element from an empty list.");
            return false;
        } // Of if
        Node tempNode = header;
        for (int i = 0; i < paraPosition; i++) {
            if (tempNode.next.next == null) {
                System.out.println("The position " + paraPosition + " is illeagal.");
                return false;
            }
            tempNode = tempNode.next;
        }
        tempNode.next = tempNode.next.next;
        return true;
    }

    public static void main(String[] args) {
        LinkedList tempFirstList = new LinkedList();
        System.out.println("Initialized, the list is: " + tempFirstList.toString());
        for (int i = 0; i < 5; i++) {
            tempFirstList.insert(0, i);
        } // Of for i
        System.out.println("Inserted, the list is: " + tempFirstList.toString());

        tempFirstList.insert(5, 9);
        System.out.println("Inserted, the list is: " + tempFirstList.toString());

        tempFirstList.delete(4);
        tempFirstList.delete(2);
        System.out.println("Deleted, the list is: " + tempFirstList.toString());
        tempFirstList.delete(0);
        System.out.println("Deleted, the list is: " + tempFirstList.toString());
        for (int i = 0; i < 5; i++) {
            tempFirstList.delete(0);
            System.out.println("Looped delete, the list is: " + tempFirstList.toString());
        }

    }
    //insert a value to a position.
}

链表的增删改查，最后的next。next把我搞晕了，再想想吧，想明白，再来改。