with Ada.Text_IO; use Ada.Text_IO;
with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;

procedure Solve is
   N : Integer;
   H : Integer;
   W : Integer;
begin
   Get (N);
   Get (H);
   Get (W);
   Put_Line (Integer'Image ((N-H+1)*(N-W+1)));
end Solve;