6
X-----------------------------------------------X
X                         X                     X
X                         X                     X
X                         X                     X
X                         X                     X
X       X      X          X                     X
X       X      X          X                     X
X       X      X          X                     X
X       X      X          X                     X
X       X      X          X      X--------------X
X       X      X          -      X              X
X       X      X                 X              X
X       X      X                 X              X
X       X      X                 X      X       X
X       X      X          X      X      X       X
X       X      X          X      -      X       X
X       X      X     b    X             X       X
X       X      X          X             X       X
X       -      X          X             X       X
X              X          X             X       X
X              X          X             X       X
X              X          X             X       X
X         X    --------------------     X       X
X         X                             X       X
X         X                             X       X
X         X                             X       X
X         X                             X       X
X         X                  X          -       X
X         X                  X                  X
X         X                  X                  X
X         X                  X                  X
X----  ---X      B    R      X     X------------X
X         X                  X     X            X
X         X                  X     _            X
X         X                  X                  X
X         X                  X                  X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
end