OJ Board

there must be something wrong with the given table

it says:
A and B represent the two primitive quilts. Each primitive quilt corresponds to a matricial arrangement of 2 x 2 characters.

but the table says:
A: it's right
/ /
/+

B: it's wrong
-
-

I think B should be :
--
--

that's my input and output, but i got wrong answer with 0.002 seconds

input:
sew ( turn(
sew(B,turn(B))),
turn(sew (turn(B),B))) ;





sew(turn(sew(B,turn(B))),A);
sew(turn (sew(A,turn(A))),
turn(turn(

turn(sew(A,turn( A ) ) ) ) ))

;

sew(A
, B ) ;
turn(B);
A;
B;



turn sew(A, B ) ;

turn(turn sew(A, B )) ;

turn(turn(turn (sew(A, B ))) ) ;
sew(turn(A),B);






A;

output:
Quilt 1:
||--
||--
--||
--||
Quilt 2:
error
Quilt 3:
\\//
+\/+
+/\+
//\\
Quilt 4:
//--
/+--
Quilt 5:
||
||
Quilt 6:
//
/+
Quilt 7:
--
--
Quilt 8:
\\
+\
||
||
Quilt 9:
--+/
--//
Quilt 10:
||
||
\+
\\
Quilt 11:
\\--
+\--
Quilt 12:
//
/+