fixed the algorithm LZ77

Author: Ulian04ka

AlgorithmsLibrary/LZ77Algm/LZ77Algm.cs

@@ -71,8 +71,8 @@ public static IAlgmEncoded<List<CodeBlock>> Encode(string inputString)
                         establishingBuffer.Append('$');
                     char nextChar = establishingBuffer[currentLengthSubString];
 
-                    string subInEstablish = establishingBuffer.Substring(0, currentLengthSubString + 1);
-                    establishingBuffer.Remove(0, length + 1);
+                    string subInEstablish = establishingBuffer.Substring(0, currentLengthSubString);
+                    establishingBuffer.Remove(0, length);
                     searchBuffer.Append(subInEstablish);
 
                     var codeblock = new CodeBlock(offset, length, nextChar);
@@ -154,6 +154,7 @@ public static IAlgmEncoded<string> Decode(string encodedString)
                     int start = resultDecoding.Length - codeBlock.Offset;
                     for (int i = 0; i <= codeBlock.Length - 1; i++)
                         resultDecoding.Append(resultDecoding[start + i]);
+                    continue;
                 }
                 resultDecoding.Append(codeBlock.NextChar);
             }