（精品课件）第六次chapter6作业（11.4评讲）.docVIP

P232 E6.2 E3. Write C++ functions to implement the following operations for the (?rst) simply linked implementation of a list: (k) remove template class List_entry Error_code ListList_entry :: remove(int position, List_entry x) { NodeList_entry *prior, *current; if (count == 0) return fail; if (position 0 | | position = count) return range_error; if (position 0) { prior = set_position(position ? 1); current = prior-next; prior-next = current-next; } else { current = head; head = head-next; } x = current-entry; delete current; count??; return success; } E5. Indicate which of the following functions are the same for doubly linked lists (as implemented in this section) and for simply linked lists. For those that are different, write new versions for doubly linked lists. Be sure that each function conforms to the specifications given in Section 6.1. Parts (f) through (h) all remain the same as for simply linked lists. (e) template class List_entry void ListList_entry :: clear( ) /* Post: The List is cleared. */ { NodeList_entry *p, *q; if (current == NULL) return; for (p = current-back; p; p = q) { q = p-back; delete p; } for (p = current; p; p = q) { q = p-next; delete p; } count = 0; current = NULL; current_position = ?1; } E3. Write implementations for the remaining String processing functions. (b) void strncpy(String copy, const String original, int n); void strncpy(String copy, const String original, unsigned n) /* Post: Copies the first n characters of String original to make String copy. */ { const char *temp = original.c_str( ); char *s = new char[n+1]; strncpy(s, temp, n); s[n] = 0; copy = s; delete []s; } 3.join two ordered list in a List, Error_code Join(List a_list,List b_list,List c_list) example : a_list=(1,3,5,7,9) b_list=(2,4,7,10,13) After the joint,c_list=(1,2,3,4,5,7,7,9,10,13) template class List_entry Error_code Join(List List_entry a_list, ListList_entry b_list, List List_entry c_list) { int i,j,k; c_list.clear(); i=0;j=0;k=0; while (ia_lis