merge-two-sorted-lists solved

Author: hsskey

merge-two-sorted-lists/hsskey.js

@@ -0,0 +1,34 @@
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} list1
+ * @param {ListNode} list2
+ * @return {ListNode}
+ */
+var mergeTwoLists = function(list1, list2) {
+    const dummy = new ListNode()
+    let tail = dummy
+
+    while(list1 && list2) {
+        if(list1.val < list2.val) {
+            tail.next = list1
+            list1 = list1.next
+        } else {
+            tail.next = list2
+            list2 = list2.next
+        }
+        tail = tail.next
+    }
+
+    if(list1) {
+        tail.next = list1
+    } else if(list2) {
+        tail.next = list2
+    }
+    return dummy.next
+};