[yayyz] WEEK 04 Solutions

merge-two-sorted-lists/yayyz.py

@@ -0,0 +1,25 @@
+# Definition for singly-linked list.
+# class ListNode:
+#     def __init__(self, val=0, next=None):
+#         self.val = val
+#         self.next = next
+class Solution:
+    def mergeTwoLists(self, list1: Optional[ListNode], list2: Optional[ListNode]) -> Optional[ListNode]:
+        dummy = ListNode(0)
+        current = dummy 
+
+        while list1 is not None and list2 is not None: 
+            if list1.val < list2.val: 
+                current.next = list1
+                list1 = list1.next
+            else:
+                current.next = list2
+                list2 = list2.next
+            current = current.next
+
+        if list1 is not None: 
+            current.next = list1
+        else:
+            current.next = list2
+
+        return dummy.next