8주차 제출

Author: jdalma

merge-two-sorted-lists/jdalma.kt

@@ -0,0 +1,45 @@
+package leetcode_study
+
+import io.kotest.matchers.shouldBe
+import org.junit.jupiter.api.Test
+
+class `merge-two-sorted-lists` {
+
+    data class ListNode(
+        var `val`: Int,
+        var next: ListNode? = null
+    )
+
+    /**
+     * TC: O(n + m), SC: O(1)
+     */
+    fun mergeTwoLists(list1: ListNode?, list2: ListNode?): ListNode? {
+        var (l1, l2) = list1 to list2
+        var current = ListNode(-1)
+        val result: ListNode = current
+
+        while (l1 != null && l2 != null) {
+            if (l1.`val` < l2.`val`) {
+                current.next = l1
+                l1 = l1.next
+            } else {
+                current.next = l2
+                l2 = l2.next
+            }
+            current.next?.let { current = it }
+        }
+
+        if (l1 != null) current.next = l1
+        if (l2 != null) current.next = l2
+
+        return result.next
+    }
+
+    @Test
+    fun `두 개의 리스트 노드를 정렬하여 병합한다`() {
+        mergeTwoLists(
+            ListNode(1,ListNode(2,ListNode(4))),
+            ListNode(1,ListNode(3,ListNode(4)))
+        ) shouldBe ListNode(1,ListNode(1,ListNode(2, ListNode(3, ListNode(4, ListNode(4))))))
+    }
+}