553d4c3a


(3.4)

prev = 0;

i k 1

{

ai = f

-1(prev, ai);

prev = (prev, ai);

}

(3.1) (3.3) , , , . (3.2) (3.4).

, . (3.1) (3.3) , (3.2) (3.4), f 1(x, y), f(x, y).

: