to to r tht = b h tht th th f .

t b th of tr or {0,1} h tht r -t -th rf of th 1.

t b th ef b th fo rr ft:

B : M; 0 ; 1 r : Fr , 01, 11 r .

r tt th: > > t hth > ttt t h th t t > rf f th t t