4주차 문제 풀이 2개 추가

- Merge Two Sorted Lists
- Maximum Depth of Binary Tree

Author: hwi-middle

maximum-depth-of-binary-tree/hwi-middle.cpp

@@ -0,0 +1,38 @@
+/**
+ * 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; // head 초기화의 복잡성을 낮추기 위한 더미노드
+        ListNode* tail = &dummy;
+
+        while (list1 != nullptr && list2 != nullptr)
+        {
+            if (list1->val < list2->val)
+            {
+                tail->next = list1;
+                list1 = list1->next;
+            }
+            else
+            {
+                tail->next = list2;
+                list2 = list2->next;
+            }
+
+            tail = tail->next;
+        }
+
+        tail->next = (list1 == nullptr) ? list2 : list1;
+
+        return dummy.next;
+    }
+}
+;

merge-two-sorted-lists/hwi-middle.cpp

@@ -0,0 +1,38 @@
+/**
+ * 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; // head 초기화의 복잡성을 낮추기 위한 더미노드
+        ListNode* tail = &dummy;
+
+        while (list1 != nullptr && list2 != nullptr)
+        {
+            if (list1->val < list2->val)
+            {
+                tail->next = list1;
+                list1 = list1->next;
+            }
+            else
+            {
+                tail->next = list2;
+                list2 = list2->next;
+            }
+
+            tail = tail->next;
+        }
+
+        tail->next = (list1 == nullptr) ? list2 : list1;
+
+        return dummy.next;
+    }
+}
+;