diff --git a/Seminars/Seminar03/Self/Task01/Program.cs b/Seminars/Seminar03/Self/Task01/Program.cs
new file mode 100644
index 0000000..92ca68e
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task01/Program.cs
@@ -0,0 +1,15 @@
+internal class program
+{
+ public static void Main()
+ {
+ Console.Write("Введите количество углов: ");
+ int n = Convert.ToInt32(Console.ReadLine());
+
+ Console.Write("Введите длину стороны: ");
+ float l = Convert.ToSingle(Console.ReadLine());
+
+ Console.Write($"Площадь фигуры равна: {(n * Math.Pow(l, 2)) / (4 * Math.Tan(Math.PI / n))}");
+
+ Console.ReadKey();
+ }
+}
\ No newline at end of file
diff --git a/Seminars/Seminar03/Self/Task01/Task01.csproj b/Seminars/Seminar03/Self/Task01/Task01.csproj
new file mode 100644
index 0000000..f02677b
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task01/Task01.csproj
@@ -0,0 +1,10 @@
+
+
+
+ Exe
+ net7.0
+ enable
+ enable
+
+
+
diff --git a/Seminars/Seminar03/Self/Task02/Program.cs b/Seminars/Seminar03/Self/Task02/Program.cs
new file mode 100644
index 0000000..701ba4d
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task02/Program.cs
@@ -0,0 +1,39 @@
+internal class Program
+{
+ public static void Main()
+ {
+ Console.Write("Введите x: ");
+ float x = Convert.ToSingle(Console.ReadLine());
+
+ Console.Write("Введите y: ");
+ float y = Convert.ToSingle(Console.ReadLine());
+
+ double length = Math.Sqrt(Math.Pow(x, 2) + Math.Pow(y, 2));
+
+
+ if (y < 0)
+ {
+ Console.WriteLine("Точка не принадлежит области");
+ Console.ReadKey();
+ return;
+ }
+ if (length > 2)
+ {
+ Console.WriteLine("Точка не принадлежит области");
+ }
+ else if (length == 2 || length == 1)
+ {
+ Console.WriteLine("Точка лежит на границе");
+ }
+ else if (length < 2 && length > 1)
+ {
+ Console.WriteLine("Точка лежит внутри области");
+ }
+ else
+ {
+ Console.WriteLine("Точка не принадлежит области");
+ }
+
+ Console.ReadKey();
+ }
+}
\ No newline at end of file
diff --git a/Seminars/Seminar03/Self/Task02/Task02.csproj b/Seminars/Seminar03/Self/Task02/Task02.csproj
new file mode 100644
index 0000000..f02677b
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task02/Task02.csproj
@@ -0,0 +1,10 @@
+
+
+
+ Exe
+ net7.0
+ enable
+ enable
+
+
+
diff --git a/Seminars/Seminar03/Self/Task03/Program.cs b/Seminars/Seminar03/Self/Task03/Program.cs
new file mode 100644
index 0000000..65ba8cb
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task03/Program.cs
@@ -0,0 +1,43 @@
+using System.ComponentModel.Design;
+
+internal class Program
+{
+ public static void Main()
+ {
+ Console.Write("Введите x: ");
+ float x = Convert.ToSingle(Console.ReadLine());
+
+ Console.Write("Введите y: ");
+ float y = Convert.ToSingle(Console.ReadLine());
+
+ double length = Math.Sqrt(Math.Pow(x, 2) + Math.Pow(y, 2));
+
+
+ if ((y < 0) && length > 1)
+ {
+ Console.WriteLine("Точка не принадлежит области");
+ }
+ else if ((y < 0) && length < 1)
+ {
+ Console.WriteLine("Точка лежит внутри области");
+ }
+ else if ((y < 0) && length == 1)
+ {
+ Console.WriteLine("Точка лежит на границе");
+ }
+ else if (length > 2)
+ {
+ Console.WriteLine("Точка не принадлежит области");
+ }
+ else if (length == 2)
+ {
+ Console.WriteLine("Точка лежит на границе");
+ }
+ else if (length < 2)
+ {
+ Console.WriteLine("Точка лежит внутри области");
+ }
+
+ Console.ReadKey();
+ }
+}
\ No newline at end of file
diff --git a/Seminars/Seminar03/Self/Task03/Task03.csproj b/Seminars/Seminar03/Self/Task03/Task03.csproj
new file mode 100644
index 0000000..f02677b
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task03/Task03.csproj
@@ -0,0 +1,10 @@
+
+
+
+ Exe
+ net7.0
+ enable
+ enable
+
+
+
diff --git a/Seminars/Seminar03/Self/Task04/Program.cs b/Seminars/Seminar03/Self/Task04/Program.cs
new file mode 100644
index 0000000..e0d0c2b
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task04/Program.cs
@@ -0,0 +1,32 @@
+internal class Program
+{
+ public static void Main()
+ {
+ Console.Write("Введите x: ");
+ int x = Convert.ToInt32(Console.ReadLine());
+
+ Console.Write("Введите y: ");
+ int y = Convert.ToInt32(Console.ReadLine());
+
+ if (x < y)
+ {
+ double F = Math.Sin(x) + Math.Pow(Math.Cos(y), 2);
+ Console.WriteLine($"x, y, F: {x}, {y}, {F}");
+ }
+ else if (x == y)
+ {
+ double F = Math.Log(Math.Abs(x));
+ Console.WriteLine($"x, y, F: {x}, {y}, {F}");
+
+ }
+ else if (x > y)
+ {
+ double F = Math.Sin(Math.Pow(x, 2)) + Math.Cos(y);
+ Console.WriteLine($"x, y, F: {x}, {y}, {F}");
+
+ }
+
+ Console.ReadLine();
+
+ }
+}
\ No newline at end of file
diff --git a/Seminars/Seminar03/Self/Task04/Task04.csproj b/Seminars/Seminar03/Self/Task04/Task04.csproj
new file mode 100644
index 0000000..f02677b
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task04/Task04.csproj
@@ -0,0 +1,10 @@
+
+
+
+ Exe
+ net7.0
+ enable
+ enable
+
+
+
diff --git a/Seminars/Seminar03/Self/Task05/Program.cs b/Seminars/Seminar03/Self/Task05/Program.cs
new file mode 100644
index 0000000..4a4032b
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task05/Program.cs
@@ -0,0 +1,45 @@
+internal class Program
+{
+ public static void Main()
+ {
+ Console.Write("Введите a: ");
+ double a = Convert.ToSingle(Console.ReadLine());
+
+ Console.Write("Введите b: ");
+ double b = Convert.ToSingle(Console.ReadLine());
+
+ Console.Write("Введите c: ");
+ double c = Convert.ToSingle(Console.ReadLine());
+
+ string s_a = a < 0 ? $"{a}" : $"+{a}";
+ string s_b = b < 0 ? $"{b}" : $"+{b}";
+ string s_c = c < 0 ? $"{c}" : $"+{c}";
+
+ Console.WriteLine($"{s_a}x^2{s_b}x{s_c}");
+
+ if (a == 0)
+ {
+ Console.WriteLine($"Единственный корень, равный {-c / b}");
+ }
+ else if (b == 0)
+ {
+ Console.WriteLine($"Два одинаковых корня, равных +-{Math.Sqrt(-c / a)}");
+ }
+ else if ((Math.Pow(b, 2) - 4 * a * c) < 0)
+ {
+ Console.WriteLine("Нет действительных корней");
+ }
+ else if ((Math.Pow(b, 2) - 4 * a * c) == 0)
+ {
+ Console.WriteLine($"Один корень, равный: {-b / (2 * a)}");
+ }
+ else if ((Math.Pow(b, 2) - 4 * a * c) > 0)
+ {
+ double D = Math.Pow(b, 2) - 4 * a * c;
+ Console.WriteLine($"Первый корень, равный: {(-b - Math.Sqrt(D))/ (2 * a)}");
+ Console.WriteLine($"Второй корень, равный: {(-b - Math.Sqrt(D)) / (2 * a)}");
+ }
+
+ Console.ReadKey();
+ }
+}
\ No newline at end of file
diff --git a/Seminars/Seminar03/Self/Task05/Task05.csproj b/Seminars/Seminar03/Self/Task05/Task05.csproj
new file mode 100644
index 0000000..f02677b
--- /dev/null
+++ b/Seminars/Seminar03/Self/Task05/Task05.csproj
@@ -0,0 +1,10 @@
+
+
+
+ Exe
+ net7.0
+ enable
+ enable
+
+
+
diff --git a/Seminars/Seminar04/Self/Task01/Program.cs b/Seminars/Seminar04/Self/Task01/Program.cs
new file mode 100644
index 0000000..c52fb60
--- /dev/null
+++ b/Seminars/Seminar04/Self/Task01/Program.cs
@@ -0,0 +1,22 @@
+internal class Program
+{
+ public static void Main()
+ {
+ string? a = Console.ReadLine();
+ char b = a[0];
+ int c = Convert.ToInt32(b);
+
+ int F = c switch
+ {
+ >= 48 and <= 57 => 100,
+ >= 65 and <= 90 => 200,
+ >= 97 and <= 122 => 300,
+ _ => 400
+ };
+
+ Console.WriteLine(F);
+ Console.ReadKey();
+
+ Console.ReadKey();
+ }
+}
\ No newline at end of file
diff --git a/Seminars/Seminar04/Self/Task01/Task01.csproj b/Seminars/Seminar04/Self/Task01/Task01.csproj
new file mode 100644
index 0000000..f02677b
--- /dev/null
+++ b/Seminars/Seminar04/Self/Task01/Task01.csproj
@@ -0,0 +1,10 @@
+
+
+
+ Exe
+ net7.0
+ enable
+ enable
+
+
+
diff --git a/Seminars/Seminar04/Self/Task02/Program.cs b/Seminars/Seminar04/Self/Task02/Program.cs
new file mode 100644
index 0000000..b77fbab
--- /dev/null
+++ b/Seminars/Seminar04/Self/Task02/Program.cs
@@ -0,0 +1,34 @@
+internal class Program
+{
+ public static void Main()
+ {
+ string? data = Console.ReadLine();
+
+ int output = data.ToLower() /* Nintendo */ switch
+ {
+ "january" or "январь" => 1,
+ "february" or "февраль" => 2,
+ "march" or "март" => 3,
+ "april" or "апрель" => 4,
+ "may" or "май" => 5,
+ "june" or "июнь" => 6,
+ "july" or "июль" => 7,
+ "august" or "август" => 8,
+ "september" or "сентябрь" => 9,
+ "october" or "октябрь" => 10,
+ "november" or "ноябрь" => 11,
+ "december" or "декабрь" => 12,
+ _ => 0
+ };
+
+ if (output == 0)
+ {
+ Console.WriteLine("В году такой месяц отсутствует");
+ Console.ReadKey();
+ return;
+ }
+
+ Console.WriteLine(output);
+ Console.ReadKey();
+ }
+}
\ No newline at end of file
diff --git a/Seminars/Seminar04/Self/Task02/Task02.csproj b/Seminars/Seminar04/Self/Task02/Task02.csproj
new file mode 100644
index 0000000..f02677b
--- /dev/null
+++ b/Seminars/Seminar04/Self/Task02/Task02.csproj
@@ -0,0 +1,10 @@
+
+
+
+ Exe
+ net7.0
+ enable
+ enable
+
+
+
diff --git a/Seminars/Seminar04/Self/Task03/Program.cs b/Seminars/Seminar04/Self/Task03/Program.cs
new file mode 100644
index 0000000..6c3970f
--- /dev/null
+++ b/Seminars/Seminar04/Self/Task03/Program.cs
@@ -0,0 +1,48 @@
+internal class Program
+{
+ public static void Main()
+ {
+ Console.Write("Введите код операции: ");
+ bool code_flag = int.TryParse(Console.ReadLine(), out int code);
+
+ if (code == 0)
+ {
+ Console.WriteLine("Некорректно введено значение кода операции");
+ Console.ReadKey();
+ return;
+ }
+
+ Console.Write("Введите A: ");
+ bool a_flag = Single.TryParse(Console.ReadLine(), out float a);
+
+ if (a == 0)
+ {
+ Console.WriteLine("Некорректно введено значение A");
+ Console.ReadKey();
+ return;
+ }
+
+ Console.Write("Введите B: ");
+ bool b_flag = Single.TryParse(Console.ReadLine(), out float b);
+
+ if (b == 0)
+ {
+ Console.WriteLine("Некорректно введено значение B");
+ Console.ReadKey();
+ return;
+ }
+
+ switch (code)
+ {
+ case 1:
+ Console.WriteLine($"{a} + {b} = {a + b}"); break;
+ case 2:
+ Console.WriteLine($"{a} - {b} = {a - b}"); break;
+ case 3:
+ Console.WriteLine($"{a} * {b} = {a * b}"); break;
+ case 4:
+ Console.WriteLine($"{a} / {b} = {a / b}"); break;
+ }
+ Console.ReadKey();
+ }
+}
\ No newline at end of file
diff --git a/Seminars/Seminar04/Self/Task03/Task03.csproj b/Seminars/Seminar04/Self/Task03/Task03.csproj
new file mode 100644
index 0000000..f02677b
--- /dev/null
+++ b/Seminars/Seminar04/Self/Task03/Task03.csproj
@@ -0,0 +1,10 @@
+
+
+
+ Exe
+ net7.0
+ enable
+ enable
+
+
+
diff --git a/Seminars/Seminar04/Self/images/Self01.JPG b/Seminars/Seminar04/Self/images/Self01.JPG
index 4ac1075..4ffe6f6 100644
Binary files a/Seminars/Seminar04/Self/images/Self01.JPG and b/Seminars/Seminar04/Self/images/Self01.JPG differ