diff --git a/Lab4/Program.cs b/Lab4/Program.cs
index 59898f2..8ceb9f4 100644
--- a/Lab4/Program.cs
+++ b/Lab4/Program.cs
@@ -4,6 +4,8 @@ public class Program
     {
         public static void Main()
         {
+            
         }
     }
 }
+
diff --git a/Lab4/Purple.cs b/Lab4/Purple.cs
index cb4bd6a..0909a8e 100644
--- a/Lab4/Purple.cs
+++ b/Lab4/Purple.cs
@@ -117,4 +117,4 @@ public void Task10(int[] array, int N)
             return (bright, normal, dim);
         }
     }
-}
\ No newline at end of file
+ }
diff --git a/Lab4/White.cs b/Lab4/White.cs
index d39815d..40e2e20 100644
--- a/Lab4/White.cs
+++ b/Lab4/White.cs
@@ -1,4 +1,4 @@
-namespace Lab4
+namespace Lab4
 {
     public class White
     {
@@ -7,7 +7,12 @@ public double Task1(int[] vector)
             double length = 0;
 
             // code here
-
+            for (int i = 0; i < vector.Length; i++)
+            {
+                length += Math.Pow(vector[i], 2);
+            }
+            length = Math.Sqrt(length);
+            Console.WriteLine(length);
             // end
 
             return length;
@@ -17,7 +22,9 @@ public int Task2(int[] array, int P, int Q)
             int count = 0;
 
             // code here
-
+            foreach (int x in array)
+            if (x > P && x < Q) count++;
+            return count;
             // end
 
             return count;
@@ -26,7 +33,26 @@ public void Task3(int[] array)
         {
 
             // code here
-
+            if (array == null || array.Length == 0)
+                return;
+            int maxIndex = 0;
+            for (int i = 0; i < array.Length; i++)
+            {
+                if (array[i] > array[maxIndex])
+                {
+                    maxIndex = i;
+                }
+            }
+            if (maxIndex == array.Length - 1) { return; }
+            
+            int min = maxIndex + 1;
+            for (int i = maxIndex + 2; i < array.Length; i++)
+            {
+                if (array[i] < array[min]) { min = i; }
+            }
+            
+            (array[maxIndex], array[min]) = (array[min], array[maxIndex]);
+            Console.WriteLine(string.Join(",", array));
             // end
 
         }
@@ -34,7 +60,16 @@ public void Task4(int[] array)
         {
 
             // code here
-
+            if (array != null && array.Length > 0)
+            {
+                int maxIndex = 0;
+                for (int i = 2; i < array.Length; i += 2)
+                {
+                    if (array[i] > array[maxIndex])
+                        maxIndex = i;
+                }
+                array[maxIndex] = maxIndex;
+            }
             // end
 
         }
@@ -43,7 +78,18 @@ public int Task5(int[] array, int P)
             int index = 0;
 
             // code here
-
+                         index = -1;
+            if (array != null)
+            {
+                for (int i = 0; i < array.Length; i++)
+                {
+                    if (array[i] == P)
+                    {
+                        index = i;
+                        break;
+                    }
+                }
+            }
             // end
 
             return index;
@@ -52,7 +98,24 @@ public void Task6(int[] array)
         {
 
             // code here
-
+             int imax = int.MinValue;
+            int IxMax = -1;
+            for (int i = 0; i < array.Length; i++)
+            {
+                if (imax < array[i])
+                {
+                    imax = array[i];
+                    IxMax = i;
+                }
+            }
+            if (IxMax == 0)
+            {
+                return;
+            }
+            for (int i = 0; i + 1 < IxMax; i += 2)
+            {
+                (array[i], array[i + 1]) = (array[i + 1], array[i]);
+            }
             // end
 
         }
@@ -61,7 +124,29 @@ public int[] Task7(int[] array)
             int[] answer = null;
 
             // code here
-
+            if (array != null)
+            {
+                int count = 0;
+                for (int i = 0; i < array.Length; i++)
+                {
+            
+                    if (array[i] >= 0)
+                    {
+                        count++;
+            
+                    }
+            
+                }
+                answer = new int[count];
+                int index = 0;
+                for (int i = 0; i < array.Length; i++)
+                {
+                    if (array[i] >= 0)
+                    {
+                        answer[index++] = array[i];
+                    }
+                }
+            }
             // end
 
             return answer;
@@ -70,7 +155,22 @@ public void Task8(int[] array)
         {
 
             // code here
-
+                  if (array == null || array.Length < 2)
+            {
+                return;
+            }
+            for (int i = 1; i < array.Length; i++)
+            {
+                int p = array[i];
+                int j = i - 1;
+                while (j >= 0 && array[j] < p)
+                {
+                    array[j + 1] = array[j];
+                    j--;
+                }
+            
+                array[j + 1] = p;
+            }
             // end
 
         }
@@ -78,16 +178,36 @@ public void Task9(int[] array)
         {
 
             // code here
-
+            {
+                int tepm, n = array.Length;
+                for (int i = 0; i < n / 2; i++)
+                {
+                    tepm = array[i];
+                    array[i] = array[n - i - 1];
+                    array[n - i - 1] = tepm;
+            
+                }
+            }
             // end
 
         }
         public int[] Task10(int[] A, int[] B)
         {
             int[] C = null;
-
-            // code here
-
+// code here
+if (A.Length == 0)
+    C = new int[A.Length];
+if (B.Length == 0)
+    C = new int[B.Length];
+C = new int[A.Length + B.Length];
+int ia = 0, ib = 0, ic = 0;
+while (ia < A.Length || ib < B.Length)
+{
+    if (ia < A.Length)
+        C[ic++] = A[ia++];
+    if (ib < B.Length)
+        C[ic++] = B[ib++];
+}
             // end
 
             return C;
@@ -97,7 +217,40 @@ public double[] Task11(double a, double b, int n)
             double[] array = null;
 
             // code here
+if (n <= 0) { return null; }
+
+if (n == 1)
+{
+    if (a == b)
+    {
+        return new double[] { a };
+    }
+    else
+    {
+        return null;
+    }
+}
+
+if (a == b) { return null; }
+
 
+array = new double[n];
+if (a < b)
+{
+    double step = (b - a) / (n - 1);
+    for (int i = 0; i < n; i++)
+    {
+        array[i] = a + i * step;
+    }
+}
+else
+{
+    double step = (a - b) / (n - 1);
+    for (int i = 0; i < n; i++)
+    {
+        array[i] = a - i * step;
+    }
+}
             // end
 
             return array;
@@ -108,10 +261,29 @@ public double[] Task12(double[] raw)
             double[] restored = null;
 
             // code here
-
+if (raw.Length < 3)
+{
+    restored = null;
+}
+else
+{
+    restored = new double[raw.Length];
+    for (int i = 0; i < raw.Length; i++)
+    {
+        if (raw[i] == -1 && raw[(i - 1 + raw.Length) % raw.Length] != -1 && raw[(i + 1) % raw.Length] != -1)
+        {
+            restored[i] = (raw[(i + 1) % raw.Length] + raw[(i - 1 + raw.Length) % raw.Length]) / 2;
+        }
+        else
+        {
+            restored[i] = raw[i];
+        }
+    }
+}
             // end
 
             return restored;
         }
     }
-}
\ No newline at end of file
+
+}