Added Task 2095

src/main/java/g2001_2100/s2095_delete_the_middle_node_of_a_linked_list/Solution.java

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+package g2001_2100.s2095_delete_the_middle_node_of_a_linked_list;
+
+// #Medium #Linked List #Two Pointers
+// 2022_05_23_Time_4_ms_(95.33%)_Space_220.1_MB_(38.17%)
+
+import com_github_leetcode.ListNode;
+
+/*
+ * Definition for singly-linked list.
+ * public class ListNode {
+ * int val;
+ * ListNode next;
+ * ListNode() {}
+ * ListNode(int val) { this.val = val; }
+ * ListNode(int val, ListNode next) { this.val = val; this.next = next; }
+ * }
+ */
+
+public class Solution {
+ public ListNode deleteMiddle(ListNode head) {
+ if (head.next == null) return null;
+ ListNode slow = head;
+ ListNode fast = head.next.next;
+ while (fast != null && fast.next != null) {
+ slow = slow.next;
+ fast = fast.next.next;
+ }
+ slow.next = slow.next.next;
+ return head;
+ }
+}

src/main/java/g2001_2100/s2095_delete_the_middle_node_of_a_linked_list/readme.md

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+2095. Delete the Middle Node of a Linked List
+
+Medium
+
+You are given the `head` of a linked list. **Delete** the **middle node** , and return *the* `head` *of the modified linked list* .
+
+The **middle node** of a linked list of size `n` is the `⌊n / 2⌋<sup>th</sup>` node from the **start** using **0-based indexing** , where `⌊x⌋` denotes the largest integer less than or equal to `x`.
+
+* For `n` = `1`, `2`, `3`, `4`, and `5`, the middle nodes are `0`, `1`, `1`, `2`, and `2`, respectively.
+
+**Example 1:**
+
+![](image/readme/1653301634882.png)
+
+**Input:** head = [1,3,4,7,1,2,6]
+
+**Output:** [1,3,4,1,2,6]
+
+**Explanation:**
+
+The above figure represents the given linked list. The indices of the nodes are written below. Since n = 7, node 3 with value 7 is the middle node, which is marked in red. We return the new list after removing this node.
+
+**Example 2:**
+
+![img](image/readme/1653301750855.png)
+
+**Input:** head = [1,2,3,4]
+
+**Output:** [1,2,4]
+
+**Explanation:** 
+
+The above figure represents the given linked list. For n = 4, node 2 with value 3 is the middle node, which is marked in red.
+
+**Example 3:**
+
+![](image/readme/1653301837206.png)
+
+**Input:** head = [1,2]
+
+**Output:** [2]
+
+**Explanation:**
+
+The above figure represents the given linked list. For n = 2, node 1 with value 1 is the middle node, which is marked in red. Node 0 with value 2 is the only node remaining after removing node 1.
+
+**Constraints:**
+
+* The number of nodes in the list is in the range `[1, 10<sup>5</sup>]`.
+* `1 <= Node.val <= 10<sup>5</sup>`

src/test/java/g2001_2100/s2095_delete_the_middle_node_of_a_linked_list/SolutionTest.java

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+package g2001_2100.s2095_delete_the_middle_node_of_a_linked_list;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+import com_github_leetcode.LinkedListUtils;
+import com_github_leetcode.ListNode;
+import java.util.Arrays;
+import org.junit.jupiter.api.Test;
+
+class SolutionTest {
+ @Test
+ void deleteMiddle() {
+ ListNode node1 = LinkedListUtils.createSinglyLinkedList(Arrays.asList(1, 3, 4, 7, 1, 2, 6));
+ assertThat(new Solution().deleteMiddle(node1).toString(), equalTo("1, 3, 4, 1, 2, 6"));
+ }
+
+ @Test
+ void deleteMiddle2() {
+ ListNode node2 = LinkedListUtils.createSinglyLinkedList(Arrays.asList(1, 2, 3, 4));
+ assertThat(new Solution().deleteMiddle(node2).toString(), equalTo("1, 2, 4"));
+ }
+
+ @Test
+ void deleteMiddle3() {
+ ListNode node3 = LinkedListUtils.createSinglyLinkedList(Arrays.asList(2, 1));
+ assertThat(new Solution().deleteMiddle(node3).toString(), equalTo("2"));
+ }
+}