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--- cpp:object_creation [2017/05/10 05:51] – [Παράδειγμα αρχικοποίησης δεικτών] gthanos
+++ cpp:object_creation [2018/05/02 10:26] – [Εναλλακτικοί τρόποι κλήσης του κατασκευαστή της κλάσης] gthanos
@@ Line 82: / Line 82: @@
 == Με χρήση του τελεστή = πριν τις αγκύλες ==
-<code c++>
+<code c++ RectangleInitialization.cpp>
 int main () {
   Rectangle rect = {5,6}; // calls Rectangle(int w, int h)
@@ Line 159: / Line 159: @@
 <code cpp Rectangle.cpp>
 #include <iostream>
+#include <cstdlib>
 using namespace std;
 class Rectangle {
   private:
-    int width, height;
+    int *width, *height;
   public:
     Rectangle(int w, int h);
-    Rectangle(int s);
+    ~Rectangle();
-    Rectangle();
-    int getWidth() const;
-    int getHeight() const;
     void setWidth(int w);
     void setHeight(int h);
-    int getArea() const;
+    int getWidth();
+    int getHeight();
+    int getArea();
 };
-Rectangle::Rectangle(int w, int h): width(w), height(h) {}
+Rectangle::Rectangle(int w, int h) {
-Rectangle::Rectangle(int s) : width(s), height(s) {}
+  width = new (nothrow) int;
-Rectangle::Rectangle(): width(0), height(0) {}
+  height = new (nothrow) int;
+  if(width == NULL || height == NULL) {
+    cerr << "Memory allocation failure!\n";
+    exit(-1);
+  }
+  *width = w; *height = h;
+  cout << "Constructing rectangle (w:"<< *width <<", h:"<<*height<<")\n";
+}
+Rectangle::~Rectangle() {
+  cout << "Destructing rectangle (w:"<< *width <<", h:"<<*height<<")\n";
+  delete width;
+  delete height;
+}
-int Rectangle::getWidth() const { return width;}
+void Rectangle::setWidth(int w) { *width = w; }
-int Rectangle::getHeight() const { return height;}
+void Rectangle::setHeight(int h) { *height = h; }
-void Rectangle::setWidth(int w) { width = w; }
+int Rectangle::getWidth() { return *width; }
-void Rectangle::setHeight(int h) { height = h; }
+int Rectangle::getHeight() { return *height; }
-int Rectangle::getArea() const { return width*height;}
+int Rectangle::getArea() { return *width * *height; }
 </code>