数据结构-链表

chenweijie · chenweijie · commit 02962dcbd1e2 · 2019-03-08T01:05:57.000+08:00
diff --git a/src/main/java/com/chen/dataStructure/linklistnode/SingleLinkedList.java b/src/main/java/com/chen/dataStructure/linklistnode/SingleLinkedList.java
@@ -2,6 +2,7 @@
 
 /**
  * 单链表的具体实现
+ *
  * @author :  chen weijie
  * @Date: 2019-02-21 11:35 PM
  */
@@ -14,7 +15,6 @@ public class SingleLinkedList {
     private Node head;
 
 
-
     private class Node {
 
         //每个节点的数据
@@ -31,38 +31,33 @@ public Node(Object data) {
 
     /**
      * 单链表的表头添加元素
+     *
      * @param data
      * @return
      */
     public Object addHead(Object data) {
 
         Node newHead = new Node(data);
-
         if (size == 0) {
             head = newHead;
         } else {
-            //新头节点的下个节点是旧的head节点
             newHead.next = head;
-            //新加入的节点为SingleLinkedList的头节点
             head = newHead;
         }
-
         size++;
-        return data;
+
+        return head;
     }
 
 
     /**
      * 删除链表头节点
+     *
      * @return
      */
     public Object deleteHead() {
-
         Object data = head.data;
-
-        //新头节点为旧头节点的下个节点
         head = head.next;
-
         size--;
         return data;
     }
@@ -75,37 +70,55 @@ public Object deleteHead() {
      */
     public Node find(Object data) {
 
-        Node curr = head;
-        //只是查找，不改变链表的个数，所以要新建tempSize变量
-        int tempSize = size;
+        Node current = head;
 
+        int tempSize = size;
         while (tempSize > 0) {
-            if (data.equals(curr.data)) {
-                return curr;
+            if (data.equals(current.data)) {
+                return current;
+            } else {
+                current = current.next;
+                tempSize--;
             }
-            curr = curr.next;
-            tempSize--;
+
         }
         return null;
+
     }
 
     /**
      * 删除指定元素，删除成功返回true
+     *
      * @param data
      * @return
      */
-    public boolean delete(Object data){
-
-
-
-
-
-
-
-
+    public boolean delete(Object data) {
 
+        if (size == 0) {
+            return true;
+        }
+        Node current = head;
+        Node previous = head;
+
+        while (current.data != data) {
+            if (current.next == null) {
+                return false;
+            } else {
+                previous = current;
+                current = current.next;
+            }
+        }
 
-        return false;
+        //如果删除的节点是第一个节点
+        if (current == head) {
+            head = current.next;
+            size--;
+        } else {
+            //删除的节点不是第一个节点
+            previous.next = current.next;
+            size--;
+        }
+        return true;
     }
 
 
@@ -119,6 +132,59 @@ public boolean isEmpty() {
     }
 
 
+    //显示节点信息
+    public void display() {
+        if (size > 0) {
+            Node node = head;
+            int tempSize = size;
+            //当前链表只有一个节点
+            if (tempSize == 1) {
+                System.out.println("[" + node.data + "]");
+                return;
+            }
+            while (tempSize > 0) {
+                if (node.equals(head)) {
+                    System.out.print("[" + node.data + "->");
+                } else if (node.next == null) {
+                    System.out.print(node.data + "]");
+                } else {
+                    System.out.print(node.data + "->");
+                }
+                node = node.next;
+                tempSize--;
+            }
+            System.out.println();
+        } else {
+            //如果链表一个节点都没有，直接打印[]
+            System.out.println("[]");
+        }
+
+    }
+
+
+    public static void main(String[] args) {
+
+        SingleLinkedList singleLinkedList = new SingleLinkedList();
+        singleLinkedList.addHead("A");
+        singleLinkedList.addHead("B");
+        singleLinkedList.addHead("C");
+        singleLinkedList.addHead("D");
+
+        singleLinkedList.display();
+
+        singleLinkedList.delete("B");
+
+        singleLinkedList.display();
+
+        System.out.println("find:" + singleLinkedList.find("D"));
+
+
+    }
+
+
+
+
+
 
 
 
diff --git a/src/main/java/com/chen/dataStructure/linklistnode/StackSingleLink.java b/src/main/java/com/chen/dataStructure/linklistnode/StackSingleLink.java
@@ -0,0 +1,35 @@
+package com.chen.dataStructure.linklistnode;
+
+/**
+ * 用单向链表实现栈
+ * 栈的pop()方法和push()方法，对应于链表的在头部删除元素deleteHead()以及在头部增加元素addHead()。
+ *
+ * @author :  chen weijie
+ * @Date: 2019-03-08 12:57 AM
+ */
+public class StackSingleLink {
+
+
+    private SingleLinkedList linkedList;
+
+
+    public StackSingleLink(SingleLinkedList linkedList) {
+        this.linkedList = linkedList;
+    }
+
+    public void push(Object data) {
+        linkedList.addHead(data);
+    }
+
+
+    public Object pop() {
+        return linkedList.deleteHead();
+    }
+
+
+    public boolean isEmpty() {
+        return linkedList.isEmpty();
+    }
+
+
+}
diff --git a/src/main/java/com/chen/dataStructure/linknode/LinkNodeTest.java b/src/main/java/com/chen/dataStructure/linknode/LinkNodeTest.java
@@ -23,10 +23,10 @@ public static void main(String[] args) {
         node2.setNext(node3);
 
     //打印反转前的列表
-        Node h =head;
-        while (null!=h){
-            System.out.println(h.getData()+" ");
-            h =h.getNext();
+        Node h = head;
+        while (null != h) {
+            System.out.println(h.getData() + " ");
+            h = h.getNext();
         }
 
         // 调用反转方法
@@ -42,31 +42,30 @@ public static void main(String[] args) {
     }
 
 
-
-
     /**
      * 遍历，将当前节点的下一个节点缓存后更改当前节点指针
      */
-    public static Node reverse(Node head){
+    public static Node reverse(Node head) {
 
-        if (head ==null)
+        if (head == null) {
             return head;
+        }
 
         //上一节点
-        Node pre =head;
+        Node pre = head;
         //当前节点
-        Node cur =head.getNext();
+        Node cur = head.getNext();
         //临时节点  用于保存当前节点的指针域（即下一节点）
         Node tmp;
 
         //当前节点为null 说明位于尾节点
-        while (cur!=null){
-            tmp =cur.getNext();
+        while (cur != null) {
+            tmp = cur.getNext();
             //反转指针域的指向
             cur.setNext(pre);
             //指针向下移动
-            pre =cur;
-            cur =tmp;
+            pre = cur;
+            cur = tmp;
         }
         // 最后将原链表的头节点的指针域置为null，还回新链表的头结点，即原链表的尾结点
         head.setNext(null);
