Solution #83 - Mridul/Edited - 16/03/2025

Problems/#83 - Remove Duplicates from Sorted List - Easy/Explanation.md

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+# Explanation of the `deleteDuplicates` Code
+
+This Java class provides a solution to remove duplicate values from a sorted singly linked list. It ensures that each value appears only once in the resulting list.
+
+---
+
+## Class: `Solution`
+
+### Method: `deleteDuplicates(ListNode head)`
+
+#### **Purpose**
+The method removes consecutive duplicate values from a sorted linked list.
+
+#### **Parameters**
+- `head`: The head node of the input linked list.
+
+#### **Logic**
+1. **Initialization**:
+   - A pointer `current` is initialized to point to the `head` of the linked list.
+
+2. **Iterative Traversal**:
+   - While `current` is not `null` and `current.next` is not `null`:
+     1. Check if the current node's value `current.val` is equal to the next node's value `current.next.val`:
+        - If true, skip the next node by updating `current.next` to `current.next.next` (removing the duplicate).
+        - If false, move the `current` pointer to the next node (`current = current.next`).
+
+3. **Return the Updated List**:
+   - Once all duplicates are removed, return the modified `head` of the linked list.
+
+---
+
+### Example Execution
+#### Input:
+A sorted linked list: `1 -> 1 -> 2 -> 3 -> 3`
+
+#### Output:
+The updated linked list: `1 -> 2 -> 3`
+
+---
+
+### Complexity Analysis
+1. **Time Complexity**:
+   - \(O(n)\): The list is traversed once, where \(n\) is the number of nodes.
+
+2. **Space Complexity**:
+   - \(O(1)\): No additional data structures are used. The operation modifies the list in place.
+
+---
+
+### Key Points
+- This solution works only for **sorted linked lists**. If the input list is unsorted, the duplicates will not be removed correctly.
+- The approach uses in-place modification, making it efficient in terms of space.
+
+---
+
+### Summary
+The `deleteDuplicates` method is a simple yet efficient way to clean up a sorted linked list by removing consecutive duplicate nodes, preserving only unique values.
+
+Time Complexity: O(n)
+Space Complexity: O(1)

Problems/#83 - Remove Duplicates from Sorted List - Easy/Solution.java

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+class Solution {
+    public ListNode deleteDuplicates(ListNode head) {
+        ListNode current = head;
+
+        while (current != null && current.next != null) {
+            if (current.val == current.next.val) {
+                current.next = current.next.next; 
+            } else {
+                current = current.next; 
+            }
+        }
+
+        return head;
+    }
+}