reverse linkedlist

budd-common/src/main/java/io/github/ehlxr/algorithm/linkedlist/ReverseLinkedList.java

@@ -0,0 +1,87 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright © 2022 xrv <xrv@live.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package io.github.ehlxr.algorithm.linkedlist;
+
+/**
+ * @author ehlxr
+ * @since 2022-03-14 07:05.
+ */
+public class ReverseLinkedList {
+    public static void main(String[] args) {
+        Node node5 = new Node(5, null);
+        Node node4 = new Node(4, node5);
+        Node node3 = new Node(3, node4);
+        Node node2 = new Node(2, node3);
+        Node node1 = new Node(1, node2);
+        Node node0 = new Node(0, node1);
+        Node root = new Node(null, node0);
+
+        Node reverse = reverse(root);
+        // root.print();
+
+        reverse.print();
+
+    }
+
+    public static Node reverse(Node root) {
+
+        Node pre = null;
+        Node cur = root;
+        while (cur != null) {
+            Node tmp = cur.next;
+
+            cur.next = pre;
+            pre = cur;
+            cur = tmp;
+            // tmp = cur.next;
+        }
+
+        return pre;
+    }
+}
+
+class Node {
+    public Integer value;
+    public Node next;
+
+    public Node(Integer value, Node next) {
+        this.next = next;
+        this.value = value;
+    }
+
+    public void print() {
+        System.out.println(this);
+        Node tmp = this.next;
+        while (tmp != null) {
+            System.out.println(tmp);
+            tmp = tmp.next;
+        }
+    }
+
+    @Override
+    public String toString() {
+        return "Node[value=" + this.value + "]";
+    }
+}