C language linked list of general operations, create, insert, traverse, delete

#include "stdlib.h" #include "stdio.h" #include "string.h" typedef struct NODE {int data;
struct Node *next;

}slist;
	Slist *creat_slist () {//1 Create a header node and initialize slist *phead = NULL by the method of tail interpolation;
	Slist *pcur = NULL;
	Slist *pm = NULL;
	int data = 0;
	Pcur = Phead = (slist *) malloc (sizeof (slist));
	Phead->data = 0;

	Phead->next = NULL;
	2 loops Create nodes, values from the Node data field input from the keyboard,//1 as the input end sign printf ("\nplease enter the data of node ( -1:quit)");

	scanf ("%d", &data);
		while (data!=-1) {PM = (slist*) malloc (sizeof (slist));
		Pm->data = data;

		Pm->next = NULL;
		Pcur->next = PM;
		Pcur = PM;
		printf ("\nplease enter the data of node ( -1:quit)");
	scanf ("%d", &data);
return phead;
	int Slist_print (slist *phead) {slist* pcur = NULL;
	if (!phead) {return-1;
	} pcur = phead->next;
		while (pcur) {printf ("%d\n", pcur->data);
	Pcur = pcur->next;
return 1;
	Insert y int slist_nodeinsert (slist *phead, int x, int y) {slist* PM = NULL before the node value is x; slist* Pcur = NULL;
	slist* pLast = NULL;
	if (!phead) {return-1;
	} pLast = Phead;

	Pcur = phead->next;
	PM = (slist*) malloc (sizeof (slist));
	Pm->data = y;

	Pm->next = NULL;
		while (pcur) {if (Pcur->data = = x) {break;
		} pLast = Pcur;
	Pcur = pcur->next;
	} pm->next = Pcur;

	Plast->next = PM;
return 1;
	///delete the node as Y of the linked list node int slist_nodedel (slist *phead, int y) {slist* pcur = NULL;
	slist* pLast = NULL;
	if (!phead) {return-1;
	} pLast = Phead;
	Pcur = phead->next;
		while (pcur) {if (Pcur->data = = y) {break;
		} pLast = Pcur;
	Pcur = pcur->next;
	} if (!pcur) {return-1;
	} Plast->next = pcur->next;
	Free (pcur);
return 1;
	int slist_destory (slist *phead) {slist* pnext = NULL;

	slist* pcur = NULL;
	if (!phead) {return-1;
	} pcur = Phead;
	
	Pnext = pcur->next;
		while (1) {free (pcur);
		Pcur = Pnext;
		if (!pcur) {break;		
	} Pnext = pnext->next;
return 1; int MaiN () {slist* phead = creat_slist ();
	if (!phead) {return-1;

	} slist_print (Phead);
	Slist_nodeinsert (Phead, 20, 19);

	Slist_print (Phead);
	Slist_nodedel (Phead, 19);

	Slist_print (Phead);

	Slist_destory (Phead);
return 0; }