Linked-list. Anyone could help to finish the function filter()?

template class List { private: // struct for singly-linked list nodes struct Node { T data; Node *next;

Node(const T &d = T{}, Node *n = nullptr) : data{d}, next{n} {} };

/* Data members of List class: a front and back pointer */ Node *front; Node *back;

public: // constructor List() { front = nullptr; back = nullptr; }

// destructor ~List() { clear(); }

/** * TODO * function: filter_leq * * description: removes all elements of the given list (lst) which * are less than or equal to a given value (cutoff) * * A list containing the removed elements is returned. * * examples: * * EX1: lst: [4, 9, 2, 4, 8, 12, 7, 3] * cutoff: 4 * * after call: * lst: [9, 8, 12, 7] * returned list: [4, 2, 4, 3] * * ----------------------------------------- * EX2: lst: [6, 5, 2, 1] * cutoff: 6 * * after call: * lst: [] * returned list: [6, 5, 2, 1] * * REQUIREMENTS: * * RUNTIME: THETA(n) where n is the length of the given list * * ORDERING: the ordering of the returned list should be the same as * in the given list * * MEMORY: for full credit, no new nodes should be allocated or deallocated; * you should just "re-use" the existing nodes. HOWEVER, you will * need to allocate a LIST structure itself (i.e., for the returned * list). * */ List *filter_leq(const T &cutoff) {

return nullptr; }