1. Linked List

2. Linked List
#include<stdio.h> #include<stdlib.h> struct node { int data; struct node *link; }; // release the nodes of a linked list void release_linked_list(struct node **head) {struct node *p; while(*head) { p = *head; *head = (*head)->link; free(p); } *head = NULL; }

3. int size(struct node *head) // return the number of nodes in a linked list { // insert your code } // insert a new node after trail // if trail == NULL, the newnode is the new head of this linked list void linked_list_insert(struct node **head, struct node* trail, int data) { struct node* p = (struct node *) malloc(sizeof(struct node)); p->data = data; if (*head) { if (trail==NULL) { p->link = *head; *head = p; } else { p->link = trail->link; trail->link = p;} else { p->link = NULL; (*head) = p; } return;

4. // delete all nodes with data=k void linked_list_delete_data(struct node **head, int k) { // insert your code } void linked_list_reverse_data(struct node **head) // return a node with data == k struct node* linked_list_find(struct node *p, int k) { while(p && p->data != k) p = p->link; return p; } void output_linked_list(struct node* head) { while(head) { printf("%d\n",head->data); head = head->link;} return;}

5. int main() // Do not modify the main program { int op,data; struct node *head = NULL; scanf("%d%d", &op,&data); while(op != 0) { switch(op) { case 1: linked_list_insert(&head,NULL,data); // insert break; case 2: linked_list_delete_data(&head, data); // delete case 3: printf("%d %s\n", data, linked_list_find(head,data) ? "found" : "not found"); // search case 4: printf("%d elements in linked list\n",size(head)); // size case 5: linked_list_reverse_data(head); // reverse all nodes case 6: output_linked_list(head); // list all nodes } release_linked_list(&head); return 0;

6. Write a function size which returns the number of nodes in a linked list.
Sample Input & Output (The black characters are input, the red characters are the output, and the blue characters are comments.)
1 1
1 2
1 3
1 4
1 5
4 0
5 elements in linked list
0 0

7. Write a function linked_list_delete_data which deletes all nodes with data == k.　
Sample Input & Output (The black characters are input, the red characters are the output, and the blue characters are comments.)
1 1
1 2
1 3
1 4
1 5
4 0
6 elements in linked list
2 1
5 0
6 0 2 3 4 5
0 0