merge two sorted list sol

Author: dylan-jung

merge-two-sorted-lists/dylan-jung.cpp

@@ -0,0 +1,32 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* mergeTwoLists(ListNode* list1, ListNode* list2) {
+        ListNode dummy;
+        ListNode* 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;
+        }
+
+        tail->next = list1 ? list1 : list2;
+
+        return dummy.next;
+    }
+};