{ 1 }
var S : string;
begin
  ReadLn(S);
  if Length(S)=6 then
     begin
       if (S[1] in['A'..'Z']) AND (S[2] in['0'..'9']) AND (S[3] in['0'..'9']) AND
          (S[4] in['0'..'9']) AND (S[5] in['A'..'Z']) AND (S[6] in['A'..'Z']) then WriteLn('Yes')
                                                                              else WriteLn('No');
     end
     else WriteLn('No');
end.