diff --git a/challenge_3/cpp/sven/README.md b/challenge_3/cpp/sven/README.md
new file mode 100644
index 000000000..3de6d7d67
--- /dev/null
+++ b/challenge_3/cpp/sven/README.md
@@ -0,0 +1,12 @@
+#Challenge_3 Solution
+
+Under Windows - using the Visual studio c++ compiler:
+To compile, run: "cl.exe src\Majority.cpp" 
+and run the resulting file with your sequence as arguments: "Majority.exe 2 3 4 3 2 3 3 3 1".
+
+cl can be found in C:\Program Files (x86)\<Visual Studio folder>\VC\bin
+(e.g. C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin)
+or you can open a visual studio command prompt which adds the correct paths to its environment.
+
+Under Linux - using the gcc compiler:
+g++ src\Majority.cpp && a.out
diff --git a/challenge_3/cpp/sven/src/Majority.cpp b/challenge_3/cpp/sven/src/Majority.cpp
new file mode 100644
index 000000000..e9ef5e605
--- /dev/null
+++ b/challenge_3/cpp/sven/src/Majority.cpp
@@ -0,0 +1,20 @@
+#include <iostream>
+#include <string>
+#include <unordered_map>
+#include <algorithm>
+
+int main(int argc, char* argv[])
+{
+	std::unordered_map<std::string, int> map;
+	std::pair<std::string, int> majority(argv[1], 1);
+
+	for (int i = 1; i < argc; ++i)
+	{
+		map[argv[i]]++;
+		if(map[argv[i]] > majority.second)
+		{
+			majority = std::pair<std::string, int>(argv[i], map[argv[i]]);
+		}
+	}
+	std::cout << majority.first << std::endl;
+}
\ No newline at end of file
diff --git a/challenge_3/csharp/sven/README.md b/challenge_3/csharp/sven/README.md
new file mode 100644
index 000000000..71ed78fd5
--- /dev/null
+++ b/challenge_3/csharp/sven/README.md
@@ -0,0 +1,8 @@
+# Challenge_3 Solution
+
+To compile run: "csc.exe src\Majority.cs" 
+and run the resulting file with your sequence as arguments: "Majority.exe 2 3 4 3 2 3 2 2 2 1".
+
+csc can be found in <windows installation folder>\Microsoft.NET\<Framework bitness>\<.NET version> 
+(e.g. C:\Windows\Microsoft.NET\Framework64\v4.0.30319)
+or you can open a visual studio command prompt which adds the correct paths to its environment.
diff --git a/challenge_3/csharp/sven/src/Majority.cs b/challenge_3/csharp/sven/src/Majority.cs
new file mode 100644
index 000000000..505d955f7
--- /dev/null
+++ b/challenge_3/csharp/sven/src/Majority.cs
@@ -0,0 +1,14 @@
+using System;
+using System.Linq;
+using System.Collections.Generic;
+
+namespace Challenge_3
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            Console.WriteLine(args.GroupBy(val => val).OrderBy(g => g.Count()).Last().Key);
+        }
+    }
+}
\ No newline at end of file
diff --git a/challenge_4/cpp/sven/README.md b/challenge_4/cpp/sven/README.md
new file mode 100644
index 000000000..fd3926ee3
--- /dev/null
+++ b/challenge_4/cpp/sven/README.md
@@ -0,0 +1,14 @@
+#Challenge_4 Solution
+
+Under Windows - using the Visual studio c++ compiler:
+To compile, run: "cl.exe src\Invert.cpp" 
+and run the resulting file with your tree as arguments in preorder position with null termination as '#' sign
+For example: "Invert.exe 4 2 1 # # 3 # # 7 6 # # 9 # #". encodes the example tree given for challenge 4
+and "Invert.exe P F B # # H G # # # S R # # Y T # W # # Z # #" encodes the tree as shown here: http://jcsites.juniata.edu/faculty/rhodes/cs2java/images/btreeTrav2.gif
+
+cl can be found in C:\Program Files (x86)\<Visual Studio folder>\VC\bin
+(e.g. C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin)
+or you can open a visual studio command prompt which adds the correct paths to its environment.
+
+Under Linux - using the gcc compiler:
+g++ src\Invert.cpp && a.out
diff --git a/challenge_4/cpp/sven/src/Invert.cpp b/challenge_4/cpp/sven/src/Invert.cpp
new file mode 100644
index 000000000..bd672188d
--- /dev/null
+++ b/challenge_4/cpp/sven/src/Invert.cpp
@@ -0,0 +1,78 @@
+#include <iostream>
+#include <string>
+#include <vector>
+#include <functional>
+
+static const std::string EMPTY = "#";
+
+struct BinaryTreeNode
+{
+	std::string value;
+	BinaryTreeNode* leftChild;
+	BinaryTreeNode* rightChild;
+};
+
+void traverseInOrder(BinaryTreeNode* root, std::function<void(BinaryTreeNode*)> func)
+{
+	if (root != nullptr)
+	{
+		traverseInOrder(root->leftChild, func);
+		traverseInOrder(root->rightChild, func);
+	}
+	func(root);
+}
+
+void traversePreOrder(BinaryTreeNode* root, std::function<void(BinaryTreeNode*)> func)
+{
+	func(root);
+	if (root != nullptr)
+	{
+		traversePreOrder(root->leftChild, func);
+		traversePreOrder(root->rightChild, func);
+	}
+}
+
+BinaryTreeNode* treeFromInputRec(BinaryTreeNode* root, std::vector<std::string>::const_iterator& pos, std::vector<std::string>::const_iterator end)
+{
+	if (*pos != EMPTY)
+	{
+		root->leftChild = treeFromInputRec(new BinaryTreeNode{ *pos, nullptr, nullptr }, ++pos, end);
+	}
+	pos++;
+	if (*pos != EMPTY)
+	{
+		root->rightChild = treeFromInputRec(new BinaryTreeNode{ *pos, nullptr, nullptr }, ++pos, end);
+	}
+	return root;
+}
+
+BinaryTreeNode* binaryTreeFromPreOrderInput(std::vector<std::string> input)
+{
+	BinaryTreeNode* root = new BinaryTreeNode{ input.front(), nullptr, nullptr };
+	return treeFromInputRec(root, ++input.cbegin(), input.cend());
+}
+
+
+int main(int argc, char* argv[])
+{
+	std::vector<std::string> treeInPreOrder(argv + 1, argv + argc);
+	BinaryTreeNode* tree = binaryTreeFromPreOrderInput(treeInPreOrder);
+	traverseInOrder(tree, [](BinaryTreeNode* node)
+	{
+		if (node)
+		{
+			auto temp = node->leftChild;
+			node->leftChild = node->rightChild;
+			node->rightChild = temp;
+		}
+	});
+
+	traversePreOrder(tree, [](BinaryTreeNode* node)
+	{
+		std::cout << (node ? node->value : EMPTY) << " ";
+	});
+	std::cout << std::endl;
+
+
+}
+
diff --git a/challenge_4/csharp/sven/README.md b/challenge_4/csharp/sven/README.md
new file mode 100644
index 000000000..d7fa12017
--- /dev/null
+++ b/challenge_4/csharp/sven/README.md
@@ -0,0 +1,10 @@
+# Challenge_4 Solution
+
+To compile run: "csc.exe src\Majority.cs" 
+and run the resulting file with your tree as arguments in preorder position with null termination as '#' sign
+For example: "Invert.exe 4 2 1 # # 3 # # 7 6 # # 9 # #". encodes the example tree given for challenge 4
+and "Invert.exe P F B # # H G # # # S R # # Y T # W # # Z # #" encodes the tree as shown here: http://jcsites.juniata.edu/faculty/rhodes/cs2java/images/btreeTrav2.gif
+
+csc can be found in <windows installation folder>\Microsoft.NET\<Framework bitness>\<.NET version> 
+(e.g. C:\Windows\Microsoft.NET\Framework64\v4.0.30319)
+or you can open a visual studio command prompt which adds the correct paths to its environment.
diff --git a/challenge_4/csharp/sven/src/Invert.cs b/challenge_4/csharp/sven/src/Invert.cs
new file mode 100644
index 000000000..e615973ef
--- /dev/null
+++ b/challenge_4/csharp/sven/src/Invert.cs
@@ -0,0 +1,71 @@
+using System;
+using System.Linq;
+using System.Collections.Generic;
+
+namespace Challenge_4
+{
+    class BinaryTreeNode
+    {
+        public BinaryTreeNode(string val, BinaryTreeNode left, BinaryTreeNode right)
+        {
+            value = val;
+            leftChild = left;
+            rightChild = right;
+        }
+        public string value;
+        public BinaryTreeNode leftChild;
+        public BinaryTreeNode rightChild;
+    }
+
+    class Program
+    {
+        const string EMPTY = "#";
+        static BinaryTreeNode binaryTreeFromPreOrderInput(ref IEnumerable<string> input)
+        {
+            BinaryTreeNode root = new BinaryTreeNode(input.ElementAt(0), null, null);
+
+            if (input.Count() > 1 && input.ElementAt(1) != EMPTY)
+            {
+                input = input.Skip(1);
+                root.leftChild = binaryTreeFromPreOrderInput(ref input);
+            }
+            input = input.Skip(1);
+            if (input.Count() > 1 && input.ElementAt(1) != EMPTY)
+            {
+                input = input.Skip(1);
+                root.rightChild = binaryTreeFromPreOrderInput(ref input);
+            }
+            return root;
+        }
+
+        static BinaryTreeNode traversePreOrder(BinaryTreeNode tree, Func<BinaryTreeNode, BinaryTreeNode> func)
+        {
+            tree = func(tree);
+            if (tree != null)
+            {
+                tree.leftChild = traversePreOrder(tree.leftChild, func);
+                tree.rightChild = traversePreOrder(tree.rightChild, func);
+            }
+            return tree;
+        }
+
+        static BinaryTreeNode traverseInOrder(BinaryTreeNode tree, Func<BinaryTreeNode, BinaryTreeNode> func)
+        {
+            if (tree != null)
+            {
+                tree.leftChild = traverseInOrder(tree.leftChild, func);
+                tree.rightChild = traverseInOrder(tree.rightChild, func);
+            }
+            return func(tree);
+        }
+
+        static void Main(string[] args)
+        {
+            IEnumerable<string> input = args.AsEnumerable();
+            BinaryTreeNode tree = binaryTreeFromPreOrderInput(ref input);
+
+            tree = traverseInOrder(tree, node => node != null ? new BinaryTreeNode(node.value, node.rightChild, node.leftChild) : null);
+            traversePreOrder(tree, node => { Console.Write((node != null ? node.value : EMPTY) + " "); return node; } );
+        }
+    }
+}
\ No newline at end of file
diff --git a/challenge_5/cpp/sven/README.md b/challenge_5/cpp/sven/README.md
new file mode 100644
index 000000000..d5e162e1b
--- /dev/null
+++ b/challenge_5/cpp/sven/README.md
@@ -0,0 +1,12 @@
+#Challenge_5 Solution
+
+Under Windows - using the Visual studio c++ compiler:
+To compile, run: "cl.exe src\Difference.cpp" 
+and run the resulting file with your sequence as arguments: "Difference.exe abcdefg bade5cgf".
+
+cl can be found in C:\Program Files (x86)\<Visual Studio folder>\VC\bin
+(e.g. C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin)
+or you can open a visual studio command prompt which adds the correct paths to its environment.
+
+Under Linux - using the gcc compiler:
+g++ src\Difference.cpp && a.out
diff --git a/challenge_5/cpp/sven/src/Difference.cpp b/challenge_5/cpp/sven/src/Difference.cpp
new file mode 100644
index 000000000..06684ea84
--- /dev/null
+++ b/challenge_5/cpp/sven/src/Difference.cpp
@@ -0,0 +1,18 @@
+#include <iostream>
+#include <string>
+#include <algorithm>
+
+int main(int argc, char* argv[])
+{
+	std::string normalString = argv[1];
+	std::string extraChar = argv[2];
+	auto it = std::find_if(extraChar.begin(), extraChar.end(), [&normalString](char c) 
+	{
+		return normalString.find(c) == std::string::npos;
+	});
+
+	std::cout << *it << std::endl;
+
+
+}
+
diff --git a/challenge_5/csharp/sven/README.md b/challenge_5/csharp/sven/README.md
new file mode 100644
index 000000000..d9f88bbf1
--- /dev/null
+++ b/challenge_5/csharp/sven/README.md
@@ -0,0 +1,8 @@
+# Challenge_5 Solution
+
+To compile run: "csc.exe src\Difference.cs" 
+and run the resulting file with your sequence as arguments: "Difference.exe abcdefg bade5cgf".
+
+csc can be found in <windows installation folder>\Microsoft.NET\<Framework bitness>\<.NET version> 
+(e.g. C:\Windows\Microsoft.NET\Framework64\v4.0.30319)
+or you can open a visual studio command prompt which adds the correct paths to its environment.
diff --git a/challenge_5/csharp/sven/src/Difference.cs b/challenge_5/csharp/sven/src/Difference.cs
new file mode 100644
index 000000000..fd10146f1
--- /dev/null
+++ b/challenge_5/csharp/sven/src/Difference.cs
@@ -0,0 +1,14 @@
+using System;
+using System.Linq;
+using System.Collections.Generic;
+
+namespace Challenge_5
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            Console.WriteLine(args[1].Except(args[0]).First());
+        }
+    }
+}
\ No newline at end of file
diff --git a/challenge_6/cpp/sven/README.md b/challenge_6/cpp/sven/README.md
new file mode 100644
index 000000000..2a58f7ded
--- /dev/null
+++ b/challenge_6/cpp/sven/README.md
@@ -0,0 +1,12 @@
+#Challenge_6 Solution
+
+Under Windows - using the Visual studio c++ compiler:
+To compile, run: "cl.exe src\Ranges.cpp" 
+and run the resulting file with your sequence as arguments: "Ranges.exe 1 2 3 5 6 10 11 12 13 20".
+
+cl can be found in C:\Program Files (x86)\<Visual Studio folder>\VC\bin
+(e.g. C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin)
+or you can open a visual studio command prompt which adds the correct paths to its environment.
+
+Under Linux - using the gcc compiler:
+g++ src\Tanges.cpp && a.out
diff --git a/challenge_6/cpp/sven/src/Ranges.cpp b/challenge_6/cpp/sven/src/Ranges.cpp
new file mode 100644
index 000000000..ab92d67c6
--- /dev/null
+++ b/challenge_6/cpp/sven/src/Ranges.cpp
@@ -0,0 +1,24 @@
+#include <iostream>
+#include <string>
+#include <algorithm>
+
+int main(int argc, char* argv[])
+{
+	int rangeBegin = std::stoi(argv[1]);
+	int rangeEnd = rangeBegin;
+	for (int i = 2; i < argc; ++i)
+	{
+		if (rangeEnd + 1 == std::stoi(argv[i]))
+		{
+			rangeEnd++;
+		}
+		else
+		{
+			std::cout << rangeBegin << "->" << rangeEnd << std::endl;
+			rangeBegin = std::stoi(argv[i]);
+			rangeEnd = rangeBegin;
+		}
+	}
+	std::cout << rangeBegin << "->" << rangeEnd << std::endl;
+}
+
diff --git a/challenge_6/csharp/sven/README.md b/challenge_6/csharp/sven/README.md
new file mode 100644
index 000000000..214898c7e
--- /dev/null
+++ b/challenge_6/csharp/sven/README.md
@@ -0,0 +1,8 @@
+# Challenge_6 Solution
+
+To compile run: "csc.exe src\Ranges.cs" 
+and run the resulting file with your sequence as arguments: "Ranges.exe 1 2 3 5 6 10 11 12 13 20".
+
+csc can be found in <windows installation folder>\Microsoft.NET\<Framework bitness>\<.NET version> 
+(e.g. C:\Windows\Microsoft.NET\Framework64\v4.0.30319)
+or you can open a visual studio command prompt which adds the correct paths to its environment.
diff --git a/challenge_6/csharp/sven/src/Ranges.cs b/challenge_6/csharp/sven/src/Ranges.cs
new file mode 100644
index 000000000..b8b40fec7
--- /dev/null
+++ b/challenge_6/csharp/sven/src/Ranges.cs
@@ -0,0 +1,31 @@
+using System;
+using System.Linq;
+using System.Collections.Generic;
+
+namespace Challenge_5
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            List<int> list = args.Select(arg => int.Parse(arg)).ToList();
+            int rangeBegin = list.First();
+            int rangeEnd = rangeBegin;
+
+            for (int i = 1; i < list.Count; i++)
+            {
+                if (rangeEnd + 1 == list[i])
+                {
+                    rangeEnd++;
+                }
+                else
+                {
+                    Console.WriteLine(rangeBegin + "->" + rangeEnd);
+                    rangeBegin = list[i];
+                    rangeEnd = rangeBegin;
+                }
+            }
+            Console.WriteLine(rangeBegin + "->" + rangeEnd);
+        }
+    }
+}
\ No newline at end of file