fix bug

ch16/ex16.14.15/Screen.h

@@ -15,11 +15,9 @@ class Screen {
     typedef std::string::size_type pos;
     Screen() = default; // needed because Screen has another constructor
     // cursor initialized to 0 by its in-class initializer
-    Screen(pos ht, pos wd, char c): height(ht), width(wd),
-                                    contents(ht * wd, c) { }
+    Screen(char c):contents(ht * wd, c) { }
     char get() const              // get the character at the cursor
         { return contents[cursor]; }       // implicitly inline
-    inline char get(pos ht, pos wd) const; // explicitly inline
     Screen &move(pos r, pos c);      // can be made inline later
 private:
     pos cursor = 0;