单链表的查找

#include<stdio.h>

#include<stdlib.h>

typedef struct LNode{
    int data;
    struct LNode *next;
}LNode, *LinkList;

LinkList List_Init(){
    LinkList p = (LinkList)malloc(sizeof(LNode));
    p->next = NULL;
    return p;
}

LinkList Get_Elem_i(LinkList L,int i){//按给定位置查找链表中数据
//带有头结点的单链表
    LinkList p = L->next;//首结点
    int j = 1;//统计个数
    if(i<0)
        return NULL;
    if(i==0)
        return L;//返回头结点
    while(p && j<i){
        p = p->next;
        j++;
    }
    return p;
}

LinkList Get_Elem_e(LinkList L,int e){//按给定值查找是否有此元素，有则返回，无则返回NULL
//带有头结点的单链表
    LinkList p = L->next;
    while(p && p->data!=e){
        p = p->next;  //找不到就继续查找
    }
    return p;//找到就返回
}

LinkList List_HeadInsert(LinkList L){
    int x;
    LinkList s;

    scanf("%d",&x);
    while(x!=9999){
        s = (LinkList)malloc(sizeof(LNode));
        s->data = x;
        s->next = L->next;
        L->next = s;
        scanf("%d",&x);
    }
    return L;
}

LinkList List_TailInsert(LinkList L){
    int x;
    LinkList r = L;
    LinkList s;

    scanf("%d",&x);
    while(x!=9999){
        s = (LinkList)malloc(sizeof(LNode));
        s->data = x;
        r->next = s;
        r = s;
        scanf("%d",&x);  
    }
    r->next = NULL;
    return L;

}

void ListTraverse(LinkList L){

	LinkList p = L->next;
	while(p){
		printf("%d ",p->data);
		p = p->next;
	}
	printf("\n");
}
int main(){
	LinkList L = List_Init();
	List_TailInsert(L);
	ListTraverse(L);

    int x = 0;
	scanf("%d",&x);

	LinkList L1 = Get_Elem_e(L,x);
	printf("%d \n",L1->data);
    return 0;
}