diff --git a/M3/commands.cpp b/M3/commands.cpp
new file mode 100644
index 0000000..713c64d
--- /dev/null
+++ b/M3/commands.cpp
@@ -0,0 +1,49 @@
+#include "commands.hpp"
+
+#include <iostream>
+
+void mas::createCircle(std::istream& in, std::map< std::string, Circle >& shapes)
+{
+  std::string name;
+  int radius = 0;
+  Point center{0.0, 0.0};
+
+  in >> name >> radius >> center.x >> center.y;
+  if (!in || radius <= 0 || shapes.find(name) != shapes.end()) {
+    throw std::invalid_argument("createCircle: invalid input");
+  }
+
+  shapes[name] = Circle{radius, center};
+}
+
+void mas::showCircle(std::istream& in, std::ostream& out, const std::map< std::string, Circle >& shapes)
+{
+  std::string name;
+
+  in >> name;
+  Circle circle = shapes.at(name);
+
+  out << circle.getRadius() << " (" << circle.getCenter().x << ' ' << circle.getCenter().y << ")\n";
+}
+
+void mas::showFrame(std::istream& in, std::ostream& out, const std::map< std::string, Circle >& shapes)
+{
+  std::string name;
+
+  in >> name;
+  Circle circle = shapes.at(name);
+
+  out << "(" << circle.getCenter().x - circle.getRadius() << ' ' << circle.getCenter().y - circle.getRadius() << ") ";
+  out << '(' << circle.getCenter().x + circle.getRadius() << ' ' << circle.getCenter().y + circle.getRadius() << ")\n";
+}
+
+void mas::spawnProcess(std::istream& in)
+{
+  std::string name;
+  int seed = 0;
+
+  in >> name >> seed;
+  if (!in || seed < 0) {
+    throw std::invalid_argument("spawnProcess: invalid input");
+  }
+}
diff --git a/M3/commands.hpp b/M3/commands.hpp
new file mode 100644
index 0000000..60f49bf
--- /dev/null
+++ b/M3/commands.hpp
@@ -0,0 +1,16 @@
+#ifndef M3_COMMANDS_HPP
+#define M3_COMMANDS_HPP
+
+#include <map>
+#include <string>
+
+#include "geometry_utils.hpp"
+
+namespace mas {
+  void createCircle(std::istream& in, std::map< std::string, Circle >& shapes);
+  void showCircle(std::istream& in, std::ostream& out, const std::map< std::string, Circle >& shapes);
+  void showFrame(std::istream& in, std::ostream& out, const std::map< std::string, Circle >& shapes);
+  void spawnProcess(std::istream& in);
+}
+
+#endif
diff --git a/M3/geometry_utils.cpp b/M3/geometry_utils.cpp
new file mode 100644
index 0000000..87f57b8
--- /dev/null
+++ b/M3/geometry_utils.cpp
@@ -0,0 +1,36 @@
+#include "geometry_utils.hpp"
+
+mas::Circle::Circle():
+  radius_(0.0),
+  center_({0.0, 0.0})
+{}
+
+mas::Circle::Circle(const Circle& rhs):
+  radius_(rhs.radius_),
+  center_({rhs.center_.x, rhs.center_.y})
+{}
+
+mas::Circle::Circle(int radius, Point center):
+  radius_(radius),
+  center_({center.x, center.y})
+{}
+
+mas::Circle& mas::Circle::operator=(const Circle& rhs)
+{
+  if (this != &rhs) {
+    radius_ = rhs.radius_;
+    center_ = rhs.center_;
+  }
+
+  return *this;
+}
+
+int mas::Circle::getRadius()
+{
+  return radius_;
+}
+
+mas::Point mas::Circle::getCenter()
+{
+  return center_;
+}
diff --git a/M3/geometry_utils.hpp b/M3/geometry_utils.hpp
new file mode 100644
index 0000000..c50c88b
--- /dev/null
+++ b/M3/geometry_utils.hpp
@@ -0,0 +1,28 @@
+#ifndef M3_GEOMETRY_UTILS_HPP
+#define M3_GEOMETRY_UTILS_HPP
+
+namespace mas {
+  struct Point
+  {
+    double x, y;
+  };
+
+  class Circle
+  {
+  public:
+    Circle();
+    Circle(const Circle& rhs);
+    Circle(int radius, Point center);
+
+    Circle& operator=(const Circle& rhs);
+
+    int getRadius();
+    Point getCenter();
+
+  private:
+    int radius_;
+    Point center_;
+  };
+}
+
+#endif
diff --git a/M3/main.cpp b/M3/main.cpp
new file mode 100644
index 0000000..892d4f0
--- /dev/null
+++ b/M3/main.cpp
@@ -0,0 +1,49 @@
+#include <functional>
+#include <iostream>
+#include <limits>
+
+#include "commands.hpp"
+
+int main()
+{
+  using namespace mas;
+
+  std::map< std::string, mas::Circle > shapes;
+
+  std::map< std::string, std::function< void() > > commands;
+  try {
+    commands["circle"] = std::bind(createCircle, std::ref(std::cin), std::ref(shapes));
+    // commands["set"] = std::bind();
+    commands["show"] = std::bind(showCircle, std::ref(std::cin), std::ref(std::cout), std::cref(shapes));
+    // commands["showset"] = std::bind();
+    commands["frame"] = std::bind(showFrame, std::ref(std::cin), std::ref(std::cout), std::cref(shapes));
+    // commands["frameset"] = std::bind();
+    // commands["spawn"] = std::bind();
+    // commands["area-on"] = std::bind();
+    // commands["status"] = std::bind();
+    // commands["wait"] = std::bind();
+  } catch (const std::bad_alloc& e) {
+    std::cerr << e.what() << '\n';
+
+    return 1;
+  }
+
+  std::string command;
+  while ((std::cin >> command) && !std::cin.eof()) {
+    try {
+      commands.at(command)();
+    } catch (const std::out_of_range&) {
+      if (std::cin.fail()) {
+        std::cin.clear(std::cin.rdstate() ^ std::ios::failbit);
+      }
+      std::cin.ignore(std::numeric_limits< std::streamsize >::max(), '\n');
+      std::cerr << "<UNKNOWN COMMAND>\n";
+    } catch (...) {
+      if (std::cin.fail()) {
+        std::cin.clear(std::cin.rdstate() ^ std::ios::failbit);
+      }
+      std::cin.ignore(std::numeric_limits< std::streamsize >::max(), '\n');
+      std::cerr << "<INVALID COMMAND>\n";
+    }
+  }
+}
diff --git a/common/clicker.cpp b/common/clicker.cpp
new file mode 100644
index 0000000..19ce029
--- /dev/null
+++ b/common/clicker.cpp
@@ -0,0 +1,13 @@
+#include "clicker.hpp"
+
+mas::Clicker::Clicker():
+  start_(std::chrono::high_resolution_clock::now())
+{}
+
+double mas::Clicker::millisec() const
+{
+  auto t = std::chrono::high_resolution_clock::now();
+  std::chrono::duration< double, std::milli > f = t - start_;
+
+  return f.count();
+}
diff --git a/common/clicker.hpp b/common/clicker.hpp
new file mode 100644
index 0000000..251efb5
--- /dev/null
+++ b/common/clicker.hpp
@@ -0,0 +1,19 @@
+#ifndef M1_CLICKER_HPP
+#define M1_CLICKER_HPP
+
+#include <chrono>
+
+namespace mas {
+  class Clicker
+  {
+  public:
+    Clicker();
+
+    double millisec() const;
+
+  private:
+    std::chrono::time_point< std::chrono::system_clock > start_;
+  };
+}
+
+#endif