In our implementation of the atRank(i) function in Code Fragment 6.18 for class NodeSequence, we wlaked from the front of the list. Present a more efficient implementation, which walks from whichever end of the list is closer to index i (c++)

(code Fragment 6.18)

which implements the ode Fragment 6.17: The definition of class NodeSequence, sequence ADT using a doubly linked list. xt, in Code Fragment 6.18, we show the implementations of the atlndex and member functions. The function atlndex(i) hops i positions to the righ in dexOf starting at the beginning, an hops t Observe th positions defined in Code Fragment 6.8. ebeginning. and returns the resuling position. The function indevo hrough the list until finding the position that matches the given position D men at the conditional "ql- p" uses the overloaded comparison operator fo // get position from index NodeSequence: Iterator NodeSequence:atlndex(int i) const f Iterator p begin(: for (int j = 0; j