diff --git a/maximum-subarray/jdalma.kt b/maximum-subarray/jdalma.kt
new file mode 100644
index 000000000..1d9517cbc
--- /dev/null
+++ b/maximum-subarray/jdalma.kt
@@ -0,0 +1,48 @@
+package leetcode_study
+
+import io.kotest.matchers.shouldBe
+import org.junit.jupiter.api.Test
+import kotlin.math.max
+
+class `maximum-subarray` {
+
+    fun maxSubArray(nums: IntArray): Int {
+        return usingDP(nums)
+    }
+
+    /**
+     * TC: O(n), SC: O(n)
+     */
+    private fun usingDP(nums: IntArray): Int {
+        val dp = IntArray(nums.size).apply {
+            this[0] = nums[0]
+        }
+
+        for (index in 1 until nums.size) {
+            dp[index] = max(nums[index], nums[index] + dp[index - 1])
+        }
+
+        return dp.max()
+    }
+
+    /**
+     * TC: O(n), SC: O(1)
+     */
+    private fun usingKadane(nums: IntArray): Int {
+        var (current, max) = nums[0] to nums[0]
+
+        for (index in 1 until nums.size) {
+            current = max(nums[index], current + nums[index])
+            max = max(max, current)
+        }
+
+        return max
+    }
+
+    @Test
+    fun `정수 배열의 하위 배열 중 가장 큰 합을 반환한다`() {
+        maxSubArray(intArrayOf(-2,1,-3,4,-1,2,1,-5,4)) shouldBe 6
+        maxSubArray(intArrayOf(1)) shouldBe 1
+        maxSubArray(intArrayOf(5,4,-1,7,8)) shouldBe 23
+    }
+}
diff --git a/number-of-connected-components-in-an-undirected-graph/jdalma.kt b/number-of-connected-components-in-an-undirected-graph/jdalma.kt
new file mode 100644
index 000000000..1a113424f
--- /dev/null
+++ b/number-of-connected-components-in-an-undirected-graph/jdalma.kt
@@ -0,0 +1,63 @@
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.util.HashSet;
+import java.util.Set;
+
+public class CountConnectedComponents {
+
+    public int countComponents(int n, int[][] edges) {
+        final int[] relation = new int[n];
+        for (int i = 0; i < n ; i++) {
+            relation[i] = i;
+        }
+
+        int result = n;
+        for (int[] edge : edges) {
+            if (union(relation, edge) == 1) {
+                result--;
+            }
+        }
+
+        return result;
+    }
+
+    private int union(int[] relation, int[] edge) {
+        int parent1 = find(relation, edge[0]);
+        int parent2 = find(relation, edge[1]);
+
+        if (parent1 == parent2) {
+            return 0;
+        }
+
+        if (parent1 < parent2) {
+            relation[parent2] = parent1;
+        } else {
+            relation[parent1] = parent2;
+        }
+        return 1;
+    }
+
+    private int find(int[] relation, int node) {
+        int result = node;
+        while (relation[result] != result) {
+            relation[result] = relation[relation[result]];
+            result = relation[result];
+        }
+        return result;
+    }
+
+    @Test
+    @DisplayName("입력받은 노드와 간선을 통해 그래프의 개수를 반환한다")
+    void graphCount() {
+        int actual = countComponents(3, new int[][]{ {0,1}, {0,2} });
+        Assertions.assertThat(actual).isEqualTo(1);
+
+        int actual1 = countComponents(6, new int[][]{ {0,1}, {1,2}, {2,3}, {4,5} });
+        Assertions.assertThat(actual1).isEqualTo(2);
+
+        int actual2 = countComponents(6, new int[][]{ {0,1}, {2,3}, {4,5}, {1,2}, {3,4} });
+        Assertions.assertThat(actual2).isEqualTo(1);
+    }
+}
diff --git a/remove-nth-node-from-end-of-list/jdalma.kt b/remove-nth-node-from-end-of-list/jdalma.kt
new file mode 100644
index 000000000..533be8797
--- /dev/null
+++ b/remove-nth-node-from-end-of-list/jdalma.kt
@@ -0,0 +1,82 @@
+package leetcode_study
+
+import io.kotest.matchers.shouldBe
+import org.junit.jupiter.api.Test
+
+class `remove-nth-node-from-end-of-list` {
+
+    fun removeNthFromEnd(head: ListNode?, n: Int): ListNode? {
+        if (head == null || (head.next == null && n == 1)) {
+            return null
+        }
+        return usingTwoPointers(head, n)
+    }
+
+    /**
+     * TC: O(n), SC: O(n)
+     */
+    private fun usingExtraList(head: ListNode, n: Int): ListNode {
+
+        fun toList(node: ListNode): List<ListNode> {
+            val list = mutableListOf<ListNode>()
+            var tmp: ListNode? = node
+            while (tmp != null) {
+                list.add(tmp)
+                tmp = tmp.next
+            }
+            return list
+        }
+
+        val list = toList(head)
+        var root = head
+        if (list.size == n) {
+            root = list[1]
+        } else {
+            list[list.size - n - 1].next = list[list.size - n].next
+        }
+        return root
+    }
+
+    /**
+     * fast를 n만큼 먼저 이동 시킨 후 fast.next가 null일 때까지 fast와 slow를 다음 노드로 이동시킨다.
+     * fast를 n만큼 이동시키면 결국 slow는 n의 이전 노드에 도달하게 되기에 해당 slow 노드의 next를 변경하면 된다.
+     * TC: O(n), SC: O(1)
+     */
+    private fun usingTwoPointers(head: ListNode, n: Int): ListNode? {
+        var fast: ListNode? = head
+        var slow: ListNode? = head
+
+        repeat(n) {
+            fast = fast?.next
+        }
+        if (fast == null) return head.next
+
+        while (fast?.next != null) {
+            fast = fast?.next
+            slow = slow?.next
+        }
+        slow?.next = slow?.next?.next
+        return head
+    }
+
+    @Test
+    fun `링크된 목록의 헤드가 주어지면 목록의 끝에서 n번째 노드를 제거하고 그 헤드를 반환합니다`() {
+        removeNthFromEnd(ListNode.of(1), 1).also {
+            it shouldBe null
+        }
+
+        removeNthFromEnd(ListNode.of(1, 2), 2).also {
+            it shouldBe ListNode(2)
+        }
+
+        removeNthFromEnd(ListNode.of(1, 2), 1)!!.also {
+            it shouldBe ListNode(1)
+            it.next shouldBe null
+        }
+
+        removeNthFromEnd(ListNode.of(1, 2, 3, 4, 5), 2)!!.also {
+            it.next!!.next!!.`val` shouldBe 3
+            it.next!!.next!!.next!!.`val` shouldBe 5
+        }
+    }
+}
diff --git a/same-tree/jdalma.kt b/same-tree/jdalma.kt
new file mode 100644
index 000000000..7ad05907b
--- /dev/null
+++ b/same-tree/jdalma.kt
@@ -0,0 +1,35 @@
+package leetcode_study
+
+import io.kotest.matchers.shouldBe
+import org.junit.jupiter.api.Test
+
+class `same-tree` {
+
+    fun isSameTree(p: TreeNode?, q: TreeNode?): Boolean {
+        return if (p == null && q == null) {
+            true
+        } else if (p == null || q == null || p.`val` != q.`val`) {
+            false
+        } else {
+            isSameTree(p.left, q.left) && isSameTree(p.right, q.right)
+        }
+    }
+
+    @Test
+    fun `두 개의 트리의 동등성을 반환한다`() {
+        isSameTree(
+            TreeNode.of(1,1,2),
+            TreeNode.of(1,1,2)
+        ) shouldBe true
+
+        isSameTree(
+            TreeNode.of(1,1,2),
+            TreeNode.of(1,1,2,3)
+        ) shouldBe false
+
+        isSameTree(
+            TreeNode.of(1,1,2),
+            TreeNode.of(1,1,3)
+        ) shouldBe false
+    }
+}
diff --git a/serialize-and-deserialize-binary-tree/jdalma.kt b/serialize-and-deserialize-binary-tree/jdalma.kt
new file mode 100644
index 000000000..b07f63ec9
--- /dev/null
+++ b/serialize-and-deserialize-binary-tree/jdalma.kt
@@ -0,0 +1,69 @@
+package leetcode_study
+
+import io.kotest.matchers.shouldBe
+import org.junit.jupiter.api.Test
+import java.util.StringJoiner
+
+/**
+ * 문제의 핵심은 트리를 탐색하는 순서 기준으로 직렬화된 문자열을 반대로 풀어내는 것
+ * 직렬화를 DFS로 해결하면 역직렬화시 선입선출 방식으로 해결하여야 하고,
+ * 직렬화를 BFS로 해결하면 역직렬화시 힙의 인덱스 규칙을 이용하여 해결할 수 있을 듯
+ */
+class `serialize-and-deserialize-binary-tree` {
+
+    private val empty = "X"
+    private val delimiter = "|"
+
+    /**
+     * DFS로 탐색하면서 노드의 값을 누적한다.
+     * TC: O(n), SC: O(n)
+     */
+    fun serialize(root: TreeNode?): String {
+        if (root == null) return ""
+
+        val joiner = StringJoiner("|")
+        nodeToString(root, joiner)
+        return joiner.toString()
+    }
+
+    private fun nodeToString(node: TreeNode?, joiner: StringJoiner) {
+        if (node == null) {
+            joiner.add(empty)
+        } else {
+            joiner.add(node.`val`.toString())
+            nodeToString(node.left, joiner)
+            nodeToString(node.right, joiner)
+        }
+    }
+
+    /**
+     * 깊이 탐색으로 누적된 문자열을 선입선출로 꺼내어 노드를 생성한다.
+     * TC: O(n), SC: O(n)
+     */
+    fun deserialize(data: String): TreeNode? {
+        if (data.isEmpty()) return null
+        return stringToNode(ArrayDeque(data.split(delimiter)))
+    }
+
+    private fun stringToNode(queue: ArrayDeque<String>): TreeNode? {
+        val value = queue.removeFirst()
+        return if (value == empty) {
+            null
+        } else {
+            val node = TreeNode(value.toInt())
+            node.left = stringToNode(queue)
+            node.right = stringToNode(queue)
+            node
+        }
+    }
+
+    @Test
+    fun `트리 노드를 직렬화한다`() {
+        serialize(TreeNode.of(1,2,3,null,null,4,5)) shouldBe "1|2|X|X|3|4|X|X|5|X|X"
+    }
+
+    @Test
+    fun `문자열을 트리 노드로 역직렬화한다`() {
+        deserialize("1|2|X|X|3|4|X|X|5|X|X") shouldBe TreeNode.of(1,2,3,null,null,4,5)
+    }
+}