diff --git a/src/main/java/linkList/ListNode.java b/src/main/java/linkList/ListNode.java
new file mode 100644
index 0000000..2492a40
--- /dev/null
+++ b/src/main/java/linkList/ListNode.java
@@ -0,0 +1,26 @@
+package linkList;
+
+import binarytree.TreeNode;
+
+/**
+ * Created by tianliangxia on 16-10-22.
+ */
+public class ListNode {
+    public int val;
+    public ListNode next=null;
+    public ListNode(int val){
+        this.val = val;
+    }
+
+    @Override
+    public String toString(){
+        StringBuilder stringBuilder = new StringBuilder();
+        ListNode node = this;
+        while (node!=null){
+            stringBuilder.append(node.val+"->");
+            node=node.next;
+        }
+        stringBuilder.delete(stringBuilder.length()-2,stringBuilder.length());
+        return stringBuilder.toString();
+    }
+}
diff --git a/src/main/java/linkList/ListNodes.java b/src/main/java/linkList/ListNodes.java
new file mode 100644
index 0000000..ee46c84
--- /dev/null
+++ b/src/main/java/linkList/ListNodes.java
@@ -0,0 +1,211 @@
+package linkList;
+
+import utils.StringUtils;
+
+/**
+ * Created by tianliangxia on 16-10-22.
+ */
+public class ListNodes {
+
+    public static ListNode construct(int[] vals){
+        if(vals == null || vals.length == 0)
+            return null;
+        ListNode root = new ListNode(0);
+        ListNode head = root;
+        for(int val: vals){
+            head.next = new ListNode(val);
+            head = head.next;
+        }
+        return root.next;
+    }
+
+    public static ListNode construct(String str){
+        if(StringUtils.isEmpty(str))
+            return null;
+        String[] vals;
+        if(str.charAt(0) == '[' && str.charAt(str.length()-1)==']'){
+            str = str.substring(1, str.length()-1);
+        }
+        if(str.contains("->")){
+            vals = str.split("->");
+        }else if(str.contains(",")){
+            vals = str.split(",");
+        }else{
+            vals = new String[1];
+            vals[0]=str;
+        }
+
+        int[] ints = new int[vals.length];
+        for(int i=0;i<ints.length;i++){
+            ints[i] = Integer.valueOf(vals[i]);
+        }
+
+        return construct(ints);
+    }
+
+    public static ListNode sort(ListNode root){
+        if(root == null || root.next == null)
+            return root;
+        ListNode mid = partition(root);
+        root = sort(root);
+        mid = sort(mid);
+        return merge(root, mid);
+    }
+
+    private static ListNode partition(ListNode head){
+        int count = 0;
+        ListNode p = head;
+        while (p!=null){
+            count++;
+            p=p.next;
+        }
+        count/=2;
+        p=head;
+        for(int i=0;i<count-1;i++){
+            p=p.next;
+        }
+        ListNode tmp = p.next;
+        p.next = null;
+        return tmp;
+    }
+    public static ListNode merge(ListNode left, ListNode right){
+        ListNode root = new ListNode(0);
+        ListNode head = root;
+        while (left!=null && right!=null){
+            if(left.val <= right.val){
+                head.next=left;
+                head=head.next;
+                left=left.next;
+            }else {
+                head.next=right;
+                head=head.next;
+                right=right.next;
+            }
+        }
+        if(left!=null){
+            head.next=left;
+        }
+        if(right!=null){
+            head.next=right;
+        }
+        return root.next;
+    }
+
+    /***
+     * 1->2->2->3  =>  1->2->3
+     * @param head
+     * @return
+     */
+    public static void removeDuplication(ListNode head){
+        if(head == null || head.next == null)
+            return ;
+
+        ListNode p = head;
+        while (p != null && p.next != null){
+            if(p.val == p.next.val){
+                p.next = p.next.next;
+            }else {
+                p=p.next;
+            }
+        }
+    }
+
+    /***
+     * 1->2->2->3   => 1->3
+     * @param head
+     * @return
+     */
+
+    public static ListNode removeDuplication2(ListNode head){
+        if(head == null || head.next == null)
+            return head;
+
+        ListNode root = new ListNode(0);
+        root.next = head;
+        ListNode pre = root;
+        while (head != null && head.next != null){
+            ListNode p = head.next;
+            while (p != null && p.val == head.val){
+                p=p.next;
+            }
+            if(p == null){
+                pre.next = p;
+            }
+            if(p == head.next){
+                head = head.next;
+                pre = pre.next;
+            }else {
+                pre.next = p;
+                head = p.next;
+            }
+        }
+
+        return root.next;
+    }
+
+    /***
+     * 判断是否有环
+     * @param root
+     * @return
+     */
+    public static boolean checkRing(ListNode root){
+        if(root == null || root.next == null)
+            return false;
+        ListNode fast = root, slow = root;
+        while (fast.next != null && fast.next.next != null){
+            fast = fast.next.next;
+            slow = slow.next;
+            if(fast == slow)
+                return true;
+        }
+        return false;
+    }
+
+    /***
+     * 修改链表指向
+     * @param head
+     * @return
+     */
+    public static boolean checkRing2(ListNode head){
+        if(head == null)
+            return false;
+        ListNode root = new ListNode(0);
+        ListNode pre = root, post;
+        while (head != null){
+            post = head.next;
+            head.next = pre;
+            pre = head;
+            head = post;
+            if(head == root)
+                return true;
+        }
+        return false;
+    }
+
+    /***
+     * 找到环的入口
+     * @param head
+     * @return
+     */
+    public static ListNode findRingEntry(ListNode head){
+        if(head == null || head.next == null)
+            return null;
+        ListNode fast = head, slow = head;
+        while (fast != null && fast.next != null){
+            fast = fast.next.next;
+            slow = slow.next;
+            if(fast == slow)
+                break;
+        }
+        if(fast == null || fast.next == null)
+            return null;
+
+        fast = head;
+        while (fast != slow){
+            fast = fast.next;
+            slow = slow.next;
+        }
+        return fast;
+    }
+
+}
diff --git a/src/test/java/linkList/ListNodesTest.java b/src/test/java/linkList/ListNodesTest.java
new file mode 100644
index 0000000..431038c
--- /dev/null
+++ b/src/test/java/linkList/ListNodesTest.java
@@ -0,0 +1,126 @@
+package linkList;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ * Created by tianliangxia on 16-10-22.
+ */
+public class ListNodesTest {
+
+    @Test
+    public void constructTest(){
+        int[] vals = new int[]{1,2,3,4,5};
+        ListNode node = ListNodes.construct(vals);
+        assertEquals(node.toString(), "1->2->3->4->5");
+    }
+
+    @Test
+    public void constructTest2(){
+        ListNode node = ListNodes.construct("1->2->3->4->5");
+        assertEquals(node.toString(), "1->2->3->4->5");
+
+        node = ListNodes.construct("1,2,3,4,5");
+        assertEquals(node.toString(), "1->2->3->4->5");
+
+        node = ListNodes.construct("[1,2,3,4,5]");
+        assertEquals(node.toString(), "1->2->3->4->5");
+
+        node = ListNodes.construct("[1->2->3->4->5]");
+        assertEquals(node.toString(), "1->2->3->4->5");
+
+        node = ListNodes.construct("1");
+        assertEquals(node.toString(), "1");
+
+        node = ListNodes.construct("[1]");
+        assertEquals(node.toString(), "1");
+
+    }
+
+
+    @Test
+    public void testSort(){
+        ListNode root = ListNodes.construct("5,4,3,2,1");
+        ListNode res = ListNodes.sort(root);
+        assertEquals("1->2->3->4->5",res.toString());
+    }
+
+    @Test
+    public void mergeTest(){
+        ListNode l1 = ListNodes.construct("1,3");
+        ListNode l2 = ListNodes.construct("2,4,6");
+        ListNode merge = ListNodes.merge(l1, l2);
+        assertEquals("1->2->3->4->6", merge.toString());
+
+        l2 = ListNodes.construct("2,4,6");
+        merge = ListNodes.merge(null, l2);
+        assertEquals("2->4->6", merge.toString());
+    }
+
+    @Test
+    public void removeDuplicationTest(){
+        ListNode root = ListNodes.construct("1,2,2,3,3,3,4");
+        ListNodes.removeDuplication(root);
+        assertEquals("1->2->3->4", root.toString());
+
+        root = ListNodes.construct("1,1");
+        ListNodes.removeDuplication(root);
+        assertEquals("1", root.toString());
+    }
+
+    @Test
+    public void removeDuplication2Test(){
+        ListNode root = ListNodes.construct("1,2,2,3,3,3,4");
+        ListNodes.removeDuplication2(root);
+        assertEquals("1->4", root.toString());
+    }
+
+    @Test
+    public void checkRing1Test(){
+        //ListNode line = ListNodes.construct("1,2,3");
+        ListNode ring = ListNodes.construct("4,5,6,7,8");
+        ListNode p = ring;
+        while (p.next != null)
+            p = p.next;
+        p.next = ring;
+
+        assertEquals(true, ListNodes.checkRing(ring));
+        assertEquals(true, ListNodes.checkRing2(ring));
+    }
+
+    @Test
+    public void checkRing1Test2(){
+        ListNode line = ListNodes.construct("1,2,3");
+        ListNode ring = ListNodes.construct("4,5,6,7,8");
+        ListNode p = ring;
+        while (p.next != null)
+            p = p.next;
+        p.next = ring;
+        p=line;
+        while (p.next != null)
+            p=p.next;
+        p.next  = ring;
+
+        assertEquals(true, ListNodes.checkRing(line));
+        assertEquals(true, ListNodes.checkRing2(line));
+    }
+
+    @Test
+    public void findRingEntryTest(){
+        ListNode line = ListNodes.construct("1,2,3");
+        ListNode ring = ListNodes.construct("4,5,6,7,8");
+        ListNode p = ring;
+        while (p.next != null)
+            p = p.next;
+        p.next = ring;
+        p=line;
+        while (p.next != null)
+            p=p.next;
+        p.next  = ring;
+        assertEquals(ring, ListNodes.findRingEntry(line));
+    }
+
+
+
+}
\ No newline at end of file