init commit

contests/7contest/2.cpp

@@ -0,0 +1,58 @@
+#include <cmath>
+#include <string>
+#include <sstream>
+
+// class Figure {
+// public:
+//     virtual double get_square() const = 0;
+//     virtual ~Figure() {};
+// };
+
+class Rectangle : Figure {
+    double a;
+    double b;
+public:
+    Rectangle(double a = 0, double b = 0) : a(a), b(b) {}
+    double get_square() const {
+        return a * b;
+    }
+    static Rectangle* make(std::string s) {
+        std::istringstream ss(s);
+        double a, b;
+        ss >> a >> b;
+
+        return new Rectangle(a, b);
+    }
+};
+
+class Square : Figure {
+    double a;
+public:
+    Square(double a = 0) : a(a) {}
+    double get_square() const {
+        return a * a;
+    }
+    static Square* make(std::string s) {
+        std::istringstream ss(s);
+        double a;
+        ss >> a;
+
+        return new Square(a);
+    }
+};
+
+class Circle : Figure {
+    double r;
+public:
+    Circle(double r = 0) : r(r) {}
+    double get_square() const {
+        return M_PI * r * r;
+    }
+    static Circle* make(std::string s) {
+        std::istringstream ss(s);
+        double r;
+        ss >> r;
+
+        return new Circle(r);
+    }
+};