diff --git a/Week_01/id_34/LeetCode_83_0.cs b/Week_01/id_34/LeetCode_83_0.cs
new file mode 100644
index 00000000..fa2286c4
--- /dev/null
+++ b/Week_01/id_34/LeetCode_83_0.cs
@@ -0,0 +1,29 @@
+    public class Solution
+    {
+        public ListNode DeleteDuplicates(ListNode head)
+        {
+            int currentValue = head.val;
+            int nextValue = 0;
+
+           
+            if(head == null|| head.next==null)
+            { return head; }
+
+            ListNode copyHead = head;
+            while(copyHead.next!=null)
+            {
+                currentValue = copyHead.val;
+                nextValue = copyHead.next.val;
+                if(currentValue==nextValue)
+                {
+                    copyHead.next = copyHead.next.next;
+                }
+                else
+                {
+                    copyHead = copyHead.next;
+                }
+            }
+
+            return head;
+        }
+    }
diff --git a/Week_01/id_34/LeetCode_905_0.cs b/Week_01/id_34/LeetCode_905_0.cs
new file mode 100644
index 00000000..2ca32675
--- /dev/null
+++ b/Week_01/id_34/LeetCode_905_0.cs
@@ -0,0 +1,38 @@
+    public class Solution
+    {
+        public int[] SortArrayByParity(int[] A)
+        {
+            if (A == null && A.Length == 0)
+            {
+                return A;
+            }
+            int indexHead = 0;
+            int indexTail = A.Length - 1;
+            int tempValue = 0;
+            while (indexHead < indexTail)
+            {
+                if (A[indexHead] % 2 == 1 && A[indexTail] % 2 == 0)
+                {
+                    tempValue = A[indexHead];
+                    A[indexHead] = A[indexTail];
+                    A[indexTail] = tempValue;
+                    indexHead++;
+                    indexTail--;
+                }
+                else if (A[indexHead] % 2 == 0 && A[indexTail] % 2 == 1)
+                {
+                    indexHead++;
+                    indexTail--;
+                }
+                else if (A[indexHead] % 2 == 1)
+                {
+                    indexTail--;
+                }
+                else if (A[indexTail] % 2 == 0)
+                {
+                    indexHead++;
+                }
+            }
+            return A;
+        }
+    }