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

procedure main is
   S: String(1..3);
begin
   S := get_line;
   if (S(2) = 'B') then S(2) := 'R';
   else S(2) := 'B';
   end if;
   put_line(S);
end main;