diff --git a/ColoredSquare.c b/ColoredSquare.c
index b130f8f..52f068b 100644
--- a/ColoredSquare.c
+++ b/ColoredSquare.c
@@ -1,13 +1,18 @@
 #include <stdlib.h>
+#include <assert.h>
 
 #include "ColoredSquare.h"
 
-void ColoredSquare_constructor (void *this)
+void ColoredSquare_constructor (void *this,
+                                double a,
+                                int color)
 {
-  printf ("ColoredSquare_constructor (%lu) called\n",
-          (unsigned long) this);
-  Square_constructor (this);
-  ((ColoredSquare *) this)->color = 0;
+  printf ("ColoredSquare_constructor (%lu, %f, %d) called\n",
+          (unsigned long) this,
+          a,
+          color);
+  Square_constructor (this, a);
+  ((ColoredSquare *) this)->color = color;
 }
 
 void ColoredSquare_copy (void *to, void *from)
@@ -21,7 +26,7 @@ void ColoredSquare_copy (void *to, void *from)
 
 void* ColoredSquare_clone (void *this)
 {
-  ColoredSquare *csquare = ColoredSquare_new ();
+  ColoredSquare *csquare = ColoredSquare_new (0.0, 0);
   printf ("ColoredSquare_clone (%lu) called\n",
           (unsigned long) this);
   ColoredSquare_copy (csquare, this);
@@ -62,7 +67,7 @@ void ColoredSquare_set_color (void *this, int color)
 }
 
 /* public */
-void* ColoredSquare_new ()
+void* ColoredSquare_new (double a, int color)
 {
   static ColoredSquare_interface vtable =
     {
@@ -77,7 +82,11 @@ void* ColoredSquare_new ()
     };
   ColoredSquare *square = malloc (sizeof (*square));
 
-  printf ("ColoredSquare_new () returns %lu\n",
+  ColoredSquare_constructor (square, a, color);
+
+  printf ("ColoredSquare_new (%f, %d) returns %lu\n",
+          a,
+          color,
           (unsigned long) square); 
 
   square->vtable = (void *) &vtable;
diff --git a/ColoredSquare.h b/ColoredSquare.h
index fbf411c..8411bb0 100644
--- a/ColoredSquare.h
+++ b/ColoredSquare.h
@@ -19,7 +19,9 @@ typedef struct ColoredSquare_interface
 
 } ColoredSquare_interface;
 
-void ColoredSquare_constructor (void *this);
+void ColoredSquare_constructor (void *this,
+                                double a,
+                                int color);
 void ColoredSquare_copy (void *to, void *from);
 void* ColoredSquare_clone (void *this);
 const char* ColoredSquare_type (void *this);
@@ -35,6 +37,6 @@ typedef struct ColoredSquare
 
 } ColoredSquare;
 
-void* ColoredSquare_new ();
+void* ColoredSquare_new (double a, int color);
 
 #endif // __COLORED_SQUARE_H__
diff --git a/Square.c b/Square.c
index 2e4de45..577d226 100644
--- a/Square.c
+++ b/Square.c
@@ -2,11 +2,12 @@
 
 #include "Square.h"
 
-void Square_constructor (void *this)
+void Square_constructor (void *this, double a)
 {
-  printf ("Square_constructor (%lu) called\n",
-          (unsigned long) this);
-  ((Square *) this)->a = 0.0;
+  printf ("Square_constructor (%lu, %f) called\n",
+          (unsigned long) this,
+          a);
+  ((Square *) this)->a = a;
 }
 
 void Square_destructor (void *this)
@@ -25,7 +26,7 @@ void Square_copy (void *to, void *from)
 
 void* Square_clone (void *this)
 {
-  Square *square = Square_new ();
+  Square *square = Square_new (0.0);
   printf ("Square_clone (%lu) called\n",
           (unsigned long) this);
   Square_copy (square, this);
@@ -97,7 +98,7 @@ double Square_diag_length (void *this)
 }
 
 /* public */
-void* Square_new ()
+void* Square_new (double a)
 {
   static Square_interface vtable =
     {
@@ -111,7 +112,10 @@ void* Square_new ()
     };
   Square *square = malloc (sizeof (*square));
 
-  printf ("Square_new () returns %lu\n",
+  Square_constructor (square, a);
+
+  printf ("Square_new (%f) returns %lu\n",
+          a,
           (unsigned long) square); 
 
   square->vtable = (void *) &vtable;
diff --git a/Square.h b/Square.h
index 74d3b4a..36252a6 100644
--- a/Square.h
+++ b/Square.h
@@ -18,7 +18,7 @@ typedef struct Square_interface
 
 } Square_interface;
 
-void Square_constructor (void *this);
+void Square_constructor (void *this, double a);
 void Square_destructor (void *this);
 void Square_copy (void *to, void *from);
 void* Square_clone (void *this);
@@ -38,6 +38,6 @@ typedef struct Square
 
 } Square;
 
-void* Square_new ();
+void* Square_new (double a);
 
 #endif // __SQUARE_H__
diff --git a/main.c b/main.c
index a5239bf..f2a9d8b 100644
--- a/main.c
+++ b/main.c
@@ -8,8 +8,8 @@ int main (int argc, char *argv[])
   int i = 0;
   Figure *fig[3];
 
-  fig[0] = Square_new ();
-  fig[1] = ColoredSquare_new ();
+  fig[0] = Square_new (1);
+  fig[1] = ColoredSquare_new (2, 2);
 
   ((ColoredSquare *) fig[1])->vtable->set_color (fig[1], 5);
   ((Square *) fig[0])->vtable->resize (fig[0], 2);