c언어를 활용한 단순 연결 리스트

#include <stdio.h>
#include <stdlib.h>

typedef int element;
typedef struct ListNode {
	element data;
	struct ListNode* link;
}ListNode;

void error(char* message) {
	fprintf(stderr, "%s\n", message);
	exit(1);
}

ListNode* insertFirst(ListNode* head, int value) {
	ListNode* p = (ListNode*)malloc(sizeof(ListNode));
	p->data = value;
	p->link = head;
	head = p;
	return head;
}

ListNode* insert(ListNode* head, ListNode* pre, element value) {
	ListNode* p = (ListNode*)malloc(sizeof(ListNode));
	p->data = value;
	p->link = pre->link;
	pre->link = p;
	return head;
}

ListNode* deleteFirst(ListNode* head) {
	ListNode* removed;
	if (head == NULL) return NULL;
	removed = head;
	head = removed->link;
	free(removed);
	return head;
}

ListNode* delete(ListNode* head, ListNode* pre) {
	ListNode* removed;
	removed = pre->link;
	pre->link = removed->link;
	free(removed);
	return head;
}

void printList(ListNode* head) {
	for (ListNode* p = head;p != NULL; p = p->link) {
		printf("%d->", p->data);
	}
	printf("NULL\n");
}

int main(void) {
	ListNode* head = NULL;

	for (int i = 0;i < 5;i++) {
		head = insertFirst(head, i);
		printList(head);
	}
	for (int i = 0;i < 5;i++) {
		head = deleteFirst(head);
		printList(head);
	}
	return 0;
}

설명 : c언어를 활용한 단순 연결 리스트