diff --git a/Lab4.ChainedWords/Knyga.txt b/Lab4.ChainedWords/Knyga.txt
new file mode 100644
index 0000000..e1b448d
--- /dev/null
+++ b/Lab4.ChainedWords/Knyga.txt
@@ -0,0 +1,7 @@
+Vienas QRSs!!?SABC V ABC
+.
+CEF FEG GOF
+
+QRS SABC
+
+
diff --git a/Lab4.ChainedWords/Lab4.ChainedWords.csproj b/Lab4.ChainedWords/Lab4.ChainedWords.csproj
new file mode 100644
index 0000000..23df604
--- /dev/null
+++ b/Lab4.ChainedWords/Lab4.ChainedWords.csproj
@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp2.1</TargetFramework>
+  </PropertyGroup>
+
+</Project>
diff --git a/Lab4.ChainedWords/Program.cs b/Lab4.ChainedWords/Program.cs
new file mode 100644
index 0000000..a66aa2d
--- /dev/null
+++ b/Lab4.ChainedWords/Program.cs
@@ -0,0 +1,18 @@
+using System;
+
+namespace Lab4.ChainedWords
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            string input = "Knyga.txt";
+            string output1 = "Rodikliai.txt";
+            string output2 = "ManoKnyga.txt";
+            string punctuation = " ,.;!?";
+            TaskUtils.ProcessChains(input, output1, punctuation);
+            TaskUtils.ProcessAligned(input, output2, punctuation);
+        }
+    }
+}
+
diff --git a/Lab4.ChainedWords/TaskUtils.cs b/Lab4.ChainedWords/TaskUtils.cs
new file mode 100644
index 0000000..806765d
--- /dev/null
+++ b/Lab4.ChainedWords/TaskUtils.cs
@@ -0,0 +1,122 @@
+using System;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+
+namespace Lab4.ChainedWords
+{
+    static class TaskUtils
+    {
+        private static MatchCollection MatchByWords(string text, string punctuation)
+        {
+            string pattern = string.Format(@"[^{0}\n]+", Regex.Escape(punctuation));
+            return Regex.Matches(text, pattern, RegexOptions.IgnoreCase);
+        }
+
+        private static MatchCollection MatchByIntegers(string text)
+        {
+            return Regex.Matches(text, @"\d+");
+        }
+
+        public static List<Tuple<int, string>> FindChains(string text, string punctuation)
+        {
+            List<Tuple<int, string>> chains = new List<Tuple<int, string>>();
+
+            bool startedChain = false;
+            int chainStart = 0;
+
+            MatchCollection matches = MatchByWords(text, punctuation);
+            for (int i = 1; i < matches.Count; i++)
+            {
+                Match prevMatch = matches[i-1];
+                Match match = matches[i];
+                bool matchesCriteria = prevMatch.Value.ToLowerInvariant().Last() == match.Value.ToLowerInvariant().First();
+
+                if (matchesCriteria && !startedChain)
+                {
+                    startedChain = true;
+                    chainStart = prevMatch.Index;
+                }
+                else if (!matchesCriteria && startedChain)
+                {
+                    startedChain = false;
+                    int line = text.Substring(0, chainStart).Count(c => c == '\n')+1;
+                    string chain = text.Substring(chainStart, match.Index-chainStart).TrimEnd('\n');
+                    chains.Add(new Tuple<int, string>(line, chain));
+                }
+            }
+
+            // Ensure that last chain gets added to list
+            if (startedChain)
+            {
+                int line = text.Substring(0, chainStart).Count(c => c == '\n')+1;
+                string chain = text.Substring(chainStart).TrimEnd('\n');
+                chains.Add(new Tuple<int, string>(line, chain));
+            }
+
+            return chains;
+        }
+
+        public static List<int> FindIntegers(string text)
+        {
+            List<int> integers = new List<int>();
+
+            MatchCollection matches = MatchByIntegers(text);
+            foreach (Match match in matches)
+            {
+                integers.Add(int.Parse(match.Value));
+            }
+
+            return integers;
+        }
+
+        public static Tuple<int, string> FindLongestChain(string text, string punctuation)
+        {
+            List<Tuple<int, string>> chains = FindChains(text, punctuation);
+
+            if (chains.Count == 0)
+            {
+                return null;
+            }
+
+            Tuple<int, string> longestChain = chains[0];
+            foreach (var pair in chains)
+            {
+                if (pair.Item2.Length > longestChain.Item2.Length)
+                {
+                    longestChain = pair;
+                }
+            }
+
+            return longestChain;
+        }
+
+        public static void ProcessChains(string inputFile, string outputFile, string punctuation)
+        {
+            string text = File.ReadAllText(inputFile, Encoding.UTF8);
+            Tuple<int, string> longestChain = FindLongestChain(text, punctuation);
+            List<int> integers = FindIntegers(text);
+
+            using (StreamWriter writer = new StreamWriter(outputFile))
+            {
+                if (longestChain != null)
+                {
+                    writer.WriteLine("Ilgiausia žodžių grandinė {0} eilutėje: {1}", longestChain.Item1, longestChain.Item2);
+                }
+                else
+                {
+                    writer.WriteLine("Nėra žodžių grandinių.");
+                }
+
+                writer.WriteLine("Yra {0} žodžiai sudaryti iš skaitmenų. Jų suma: {1}", integers.Count, integers.Sum());
+            }
+        }
+
+        public static void ProcessAligned(string input, string ouput, string punctuation)
+        {
+        }
+    }
+}
+