[ PS ] : Merge Two Sorted Lists

Author: uraflower

merge-two-sorted-lists/uraflower.js

@@ -0,0 +1,40 @@
+/**
+ * Definition for singly-linked list.
+ */
+function ListNode(val, next) {
+    this.val = (val === undefined ? 0 : val)
+    this.next = (next === undefined ? null : next)
+}
+
+/**
+ * 주어진 두 연결 리스트를 하나의 정렬 리스트로 병합해 반환하는 함수
+ * @param {ListNode} list1
+ * @param {ListNode} list2
+ * @return {ListNode}
+ */
+const mergeTwoLists = function (list1, list2) {
+    let head = new ListNode(-1, null);
+    let mergedList = head;
+
+    let node1 = list1;
+    let node2 = list2;
+
+    while (node1 && node2) {
+        if (node1.val >= node2.val) {
+            mergedList.next = node2;
+            node2 = node2.next;
+        } else if (node1.val < node2.val) {
+            mergedList.next = node1;
+            node1 = node1.next;
+        }
+
+        mergedList = mergedList.next;
+    }
+
+    mergedList.next = node1 ?? node2;
+
+    return head.next;
+};
+
+// 시간복잡도: O(n)
+// 공간복잡도: O(n)