fix 21,提交148

Author: MistRay

leetcode/src/main/java/com/mistray/link/MergeTwoSortedLists21.java

@@ -30,7 +30,7 @@ public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
             l1.next = mergeTwoLists(l1.next, l2);
             return l1;
         } else {
-            l2.next = mergeTwoLists(l2.next, l2);
+            l2.next = mergeTwoLists(l2.next, l1);
             return l2;
         }
 

leetcode/src/main/java/com/mistray/link/SortList148.java

@@ -0,0 +1,48 @@
+package com.mistray.link;
+
+/**
+ * @author ZJY(MistRay)
+ * @Project algorithm-study
+ * @Package com.mistray.link
+ * @create 2020年03月04日 16:44
+ * @Desc
+ */
+public class SortList148 {
+
+    public ListNode sortList(ListNode head) {
+        if (head == null || head.next == null) {
+            return head;
+        }
+        ListNode fast = head, slow = head;
+        while (fast.next != null) {
+            fast = fast.next.next;
+            if (fast == null) {
+                break;
+            }
+            slow = slow.next;
+        }
+        ListNode right = slow.next;
+        slow.next = null;
+        ListNode l1 = sortList(head);
+        ListNode l2 = sortList(right);
+        return mergeTwoList(l1, l2);
+    }
+
+
+    // 该函数可以合并两个链表,并返回头结点
+    public ListNode mergeTwoList(ListNode l1, ListNode l2) {
+        if (l1 == null) {
+            return l2;
+        }
+        if (l2 == null) {
+            return l1;
+        }
+        if (l1.val > l2.val) {
+            l2.next = mergeTwoList(l2.next, l2);
+            return l2;
+        } else {
+            l1.next = mergeTwoList(l1.next, l2);
+            return l1;
+        }
+    }
+}