BUPT-homework/semester2/pset2/3-subLinkedList.c

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

typedef struct Node {
	int data;
	struct Node *next;
} Node;

Node *constructLinkedList();
Node *appendLinkedList(Node *ptr, int data);
void deleteLinkedList(Node *head);

int main(void) {
	Node *listA = constructLinkedList();
	Node *listB = constructLinkedList();

	Node *ptrA = listA, *ptrB, *ptrC;

	int matched = 0;

	while (ptrA != NULL) {
		matched = 0;
		ptrB = listB;

		if (ptrA->data == ptrB->data) {
			matched = 1;
			ptrC = ptrA;

			while (ptrB != NULL) {
				if (ptrC == NULL) {
					matched = 0;
					break;
				}
				if (ptrC->data != ptrB->data) {
					matched = 0;
					break;
				}
				ptrB = ptrB->next;
				ptrC = ptrC->next;

			}

		}

		if (matched == 1) {
			break;
		}

		ptrA = ptrA->next;
	}

	if (matched) {
		printf("ListB is the sub sequence of ListA.");
	} else {
		printf("ListB is not the sub sequence of ListA.");
	}

	deleteLinkedList(listA);
	deleteLinkedList(listB);
	return 0;
}

Node *constructLinkedList() {
	Node *head = malloc(sizeof(struct Node));
	int buf;
	scanf("%d", &buf);

	head->data = buf;
	head->next = NULL;
	Node *ptr = head;
	
	scanf("%d", &buf);
	while (buf != -1) {
		ptr = appendLinkedList(ptr, buf);
		scanf("%d", &buf);
	}

	return head;
}

Node *appendLinkedList(Node *ptr, int data) {
	Node *new = malloc(sizeof(Node));

	new->data = data;
	new->next = NULL;

	ptr->next = new;

	return new;
}

void deleteLinkedList(Node *head) {
	if (head == NULL) {
		return;
	} else {
		deleteLinkedList(head->next);
		free(head);
	}
}