some more solves

contests/7contest/2.cpp

@@ -9,14 +9,14 @@
 // };
 
 class Rectangle : Figure {
-    double a;
-    double b;
+    double a = 0;
+    double b = 0;
 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) {
+    static Rectangle* make(const std::string& s) {
         std::istringstream ss(s);
         double a, b;
         ss >> a >> b;
@@ -26,13 +26,13 @@ public:
 };
 
 class Square : Figure {
-    double a;
+    double a = 0;
 public:
     Square(double a = 0) : a(a) {}
     double get_square() const {
         return a * a;
     }
-    static Square* make(std::string s) {
+    static Square* make(const std::string& s) {
         std::istringstream ss(s);
         double a;
         ss >> a;
@@ -42,13 +42,13 @@ public:
 };
 
 class Circle : Figure {
-    double r;
+    double r = 0;
 public:
     Circle(double r = 0) : r(r) {}
     double get_square() const {
         return M_PI * r * r;
     }
-    static Circle* make(std::string s) {
+    static Circle* make(const std::string& s) {
         std::istringstream ss(s);
         double r;
         ss >> r;