diff --git a/appveyor.yml b/appveyor.yml
new file mode 100644
index 0000000..e7e7cb3
--- /dev/null
+++ b/appveyor.yml
@@ -0,0 +1,6 @@
+image: Visual Studio 2019
+
+build_script: 
+    - For /R %%I in (*.sln) do dotnet test %%I
+
+test: off
\ No newline at end of file
diff --git a/hw1BWT/hw1BWT.sln b/hw1BWT/hw1BWT.sln
new file mode 100644
index 0000000..bd7f4a5
--- /dev/null
+++ b/hw1BWT/hw1BWT.sln
@@ -0,0 +1,25 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.31005.135
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "hw1BWT", "hw1BWT\hw1BWT.csproj", "{0C32A11B-52F3-43CB-902C-90E3FCC9BA8E}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{0C32A11B-52F3-43CB-902C-90E3FCC9BA8E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{0C32A11B-52F3-43CB-902C-90E3FCC9BA8E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{0C32A11B-52F3-43CB-902C-90E3FCC9BA8E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{0C32A11B-52F3-43CB-902C-90E3FCC9BA8E}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {921A791C-3E9C-4F52-8699-DB40DAFD590A}
+	EndGlobalSection
+EndGlobal
diff --git a/hw1BWT/hw1BWT/BWT.cs b/hw1BWT/hw1BWT/BWT.cs
new file mode 100644
index 0000000..c5893a3
--- /dev/null
+++ b/hw1BWT/hw1BWT/BWT.cs
@@ -0,0 +1,124 @@
+using System;
+using System.Linq;
+
+namespace hw1BWT
+{
+    static class BWT
+    {
+        public static bool Test()
+        {
+            string string1 = "abcab";
+            var (result, numberOfString) = BWTtransform(string1);
+            if (result != "cbaab")
+            {
+                return false;
+            }
+            string oldString1 = ReverseBWT("cbaab", numberOfString);
+            return oldString1 == string1;
+        }
+
+        private static int[] WriteSuffixArray(string str)
+        {
+            var suffixArray = new int[str.Length];
+            for (int i = 0; i < str.Length; i++)
+            {
+                suffixArray[i] = i;
+            }
+            return suffixArray;
+        }
+
+        public static Tuple<string, int> BWTtransform(string str)
+        {
+            var suffixArray = WriteSuffixArray(str);
+            for (int i = 1; i < suffixArray.Length; i++)
+            {
+                for (int j = 0; j < suffixArray.Length - i; j++)
+                {
+                    string str1 = str.Substring(suffixArray[j]) + str.Substring(0, suffixArray[j]);
+                    string str2 = str.Substring(suffixArray[j + 1]) + str.Substring(0, suffixArray[j + 1]);
+                    if (String.Compare(str1, str2) > 0)
+                    {
+                        int swaper = suffixArray[j];
+                        suffixArray[j] = suffixArray[j + 1];
+                        suffixArray[j + 1] = swaper;
+                    }
+                }
+            }
+            string result = "";
+            var strSize = str.Length;
+            for (int i = 0; i < suffixArray.Length; i++)
+            {
+                if (suffixArray[i] == 0)
+                {
+                    result += str[strSize - 1];
+                }
+                else
+                {
+                    result += str[suffixArray[i] - 1];
+                }
+            }
+            return new Tuple<string, int>(result, Array.IndexOf(suffixArray, 0));
+        }
+
+        private static char[] GetAlphabet(char[] str)
+        {
+            string alphabet = "";
+            for (int i = 0; i < str.Length; ++i)
+            {
+                if (!alphabet.Contains(str[i]))
+                {
+                    alphabet += str[i];
+                }
+            }
+            char[] alphabetArray = alphabet.ToCharArray(0, alphabet.Length);
+            Array.Sort(alphabetArray);
+            return alphabetArray;
+        }
+
+        public static string ReverseBWT(string str, int numberOfStr)
+        {
+            char[] line = str.ToCharArray(0, str.Length);
+            char[] alphabetOfString = GetAlphabet(line);
+            var countSymbolsInStr = new int[alphabetOfString.Length];
+            for (int i = 0; i < alphabetOfString.Length; ++i)
+            {
+                countSymbolsInStr[i] = line.Where(x => x == alphabetOfString[i]).Count();
+            }
+            var numerationSymbols = new int[alphabetOfString.Length];
+            int sumSymbols = 0;
+            for (int i = 0; i < countSymbolsInStr.Length; ++i)
+            {
+                sumSymbols += countSymbolsInStr[i];
+                if (i == 0)
+                {
+                    numerationSymbols[i] = 0;
+                }
+                else
+                {
+                    numerationSymbols[i] = sumSymbols - countSymbolsInStr[i];
+                }
+            }
+            var helper = new int[line.Length];
+            for (int i = 0; i < line.Length; i++)
+            {
+                for (int j = 0; j < alphabetOfString.Length; j++)
+                {
+                    if (line[i] == alphabetOfString[j])
+                    {
+                        helper[i] = numerationSymbols[j];
+                        numerationSymbols[j]++;
+                    }
+                }
+            }
+            var answer = new char[line.Length];
+            for (int i = line.Length - 1; i > -1; i--)
+            {
+                answer[i] = line[numberOfStr];
+                numberOfStr = helper[numberOfStr];
+            }
+            var result = new String(answer);
+            result = result.Substring(0, result.Length);
+            return result;
+        }
+    }
+}
\ No newline at end of file
diff --git a/hw1BWT/hw1BWT/Program.cs b/hw1BWT/hw1BWT/Program.cs
new file mode 100644
index 0000000..35024f6
--- /dev/null
+++ b/hw1BWT/hw1BWT/Program.cs
@@ -0,0 +1,24 @@
+using System;
+using System.Linq;
+
+namespace hw1BWT
+{
+    class Program
+    {
+        static void Main()
+        {
+            if (!BWT.Test())
+            {
+                Console.WriteLine("Тест не пройден!");
+                return;
+            }
+            Console.WriteLine("Тест пройден!");
+            Console.WriteLine("Введите строку: ");
+            string line = Console.ReadLine();
+            var (result, numberOfString) = BWT.BWTtransform(line);
+            Console.WriteLine("Строка после алгоритма: " + result);
+            string res2 = BWT.ReverseBWT(result, numberOfString);
+            Console.WriteLine("Исходная строка: " + res2);
+        }
+    }
+}
\ No newline at end of file
diff --git a/hw1BWT/hw1BWT/hw1BWT.csproj b/hw1BWT/hw1BWT/hw1BWT.csproj
new file mode 100644
index 0000000..c73e0d1
--- /dev/null
+++ b/hw1BWT/hw1BWT/hw1BWT.csproj
@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+  </PropertyGroup>
+
+</Project>