diff --git a/work/week6/series/homework2/README.md b/work/week6/series/homework2/README.md
index d6f8292..1faa57c 100644
--- a/work/week6/series/homework2/README.md
+++ b/work/week6/series/homework2/README.md
@@ -1,23 +1,23 @@
 ### Work division strategy (3 people)
 
 1. Definition of top-level code interface:
 - Tristan: Series class (`series.hh`)
 - Théo: define DumperSeries class (`dumper.hh`)
 
 2. Definition and implementation of Series subclasses:
 - Tristan: ComputePi class (`pi.hh` and `pi.cc`)
-- Théo: ComputeAlgebraic class (`algebraic.hh` and `algebraic.cc`)
+- Théo: ComputeArithmetic class (`arithmetic.hh` and `arithmetic.cc`)
 - Théo: modification of main to execute series (`main.cc`)
 
 3. Definition and implementation of DumperSeries subclasses:
 - Tristan: PrintSeries class (`print.hh` and `print.cc`)
 - Théo: WriteSeries class (`write.hh` and `write.cc`)
 
 4. Re-definition of printing methods in DumperSeries:
 - Tristan: modify DumperSeries and PrintSeries classes
 
 5. Evluation of complexity:
 - Théo: modify Series, ComputePi and ComputeArithmetic classes to optimize computation
 
 6. "Bonus":
 - Flavio: Implementation of exhaustive, robust testing and options in main file
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diff --git a/work/week6/series/homework2/src/CMakeLists.txt b/work/week6/series/homework2/src/CMakeLists.txt
index dbeb35f..bde1bec 100644
--- a/work/week6/series/homework2/src/CMakeLists.txt
+++ b/work/week6/series/homework2/src/CMakeLists.txt
@@ -1 +1,5 @@
-add_executable(main main.cc)
+add_executable(main
+	main.cc
+	arithmetic.cc
+	series.hh
+)
diff --git a/work/week6/series/homework2/src/arithmetic.cc b/work/week6/series/homework2/src/arithmetic.cc
new file mode 100644
index 0000000..1cc72a5
--- /dev/null
+++ b/work/week6/series/homework2/src/arithmetic.cc
@@ -0,0 +1,11 @@
+#include <iostream>
+#include "arithmetic.hh"
+
+
+double ComputeArithmetic::compute(unsigned int N) {
+    double sum = 0;
+    for (float k = 1; k < N + 1; k++){
+        sum += k;
+    }
+    return sum;
+}
diff --git a/work/week6/series/homework2/src/arithmetic.hh b/work/week6/series/homework2/src/arithmetic.hh
new file mode 100644
index 0000000..f5c712f
--- /dev/null
+++ b/work/week6/series/homework2/src/arithmetic.hh
@@ -0,0 +1,16 @@
+#ifndef ARITHMETIC_HH
+#define ARITHMETIC_HH
+
+#include "series.hh"
+
+class ComputeArithmetic: public Series {
+	public:
+		ComputeArithmetic() : Series() {};         // Constructor
+		virtual ~ComputeArithmetic() {};           // Destructor
+
+	public:
+		double compute(unsigned int N) override;   // Defined compute method
+
+};
+
+#endif
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diff --git a/work/week6/series/homework2/src/main.cc b/work/week6/series/homework2/src/main.cc
index bb54486..a0f14ca 100644
--- a/work/week6/series/homework2/src/main.cc
+++ b/work/week6/series/homework2/src/main.cc
@@ -1,11 +1,20 @@
 #include <iostream>
+#include "arithmetic.hh"
 
 
 /* -------------------------------------------------------------------------- */
 
-
 int main(int argc, char ** argv) {
-    // Hello
-    std::cout << "Hello world"<< std::endl;
+
+    // Parse number of iterations
+    unsigned int N = 10;
+    if (argc > 1) {
+        N = atoi(argv[1]);
+    }
+
+    // Instanciate series object and compute series
+    ComputeArithmetic ar;
+    std::cout << "ComputeArithmetic("<< N << ") = " << ar.compute(N) << std::endl;
+
     return EXIT_SUCCESS;
 }
diff --git a/work/week6/series/homework2/src/series.hh b/work/week6/series/homework2/src/series.hh
index 8edb725..6f7b2fb 100644
--- a/work/week6/series/homework2/src/series.hh
+++ b/work/week6/series/homework2/src/series.hh
@@ -1,10 +1,13 @@
+#ifndef SERIES_HH
+#define SERIES_HH
+
 class Series {
-public:
-  // Constructor
-  Series();
-  // Destructor
-  virtual ~Series();
+	public:
+		Series() {};                                     // Constructor
+		virtual ~Series() {};                            // Destructor
+
+	public:
+		virtual double compute(unsigned int N) = 0;      // Virtual compute method
+};
 
-public:
-virtual double compute(unsigned int N) = 0;
-};
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+#endif
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