链表的创建和遍历

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

typedef struct Node{
    int data;        //数据域
    struct Node * pNext;    //指针域
}NODE, * PNODE;        //NODE等价于struct Node, * PNODE等价于struct Node *

PNODE createList();
void traverseList(PNODE pHead);

int main()
{

    PNODE pHead = NULL;        //等价于struct Node * pHead = NULL;
    pHead = createList();    //createList()函数功能：创建一个非循环单链表
                            //并将该链表的头节点的地址赋给pHead
    traverseList(pHead);    //
    
    system("pause");
    return 0;
}

PNODE createList(void){
    int len;    //用来存放有效节点的个数
    int i;
    int val;    //用来临时存放用户输入的节点的值
    
    //分配了一个不存放有效数据的头节点
    PNODE pHead = (PNODE)malloc(sizeof(NODE));
    if(NULL == pHead){
        printf("分配失败！\n");
        exit(-1);
    }
    
    //创建一个永远指向尾节点的指针
    PNODE pTail = pHead;    
    pTail->pNext = NULL;        
    
    printf("请输入您需要生成的链表节点的个数：len = ");
    scanf("%d", &len);

    
    for(i = 0; i < len; ++i){
        printf("请输入第%d个节点的值：", i+1);
        scanf("%d", &val);
        
        PNODE pNew  = (PNODE)malloc(sizeof(NODE));
        if(NULL == pNew){
        printf("分配失败！\n");
        exit(-1);
        }
        pNew->data = val;
        pTail->pNext = pNew;
        pNew->pNext = NULL;
        pTail = pNew;
        
    }
    return pHead;
} 

void traverseList(PNODE pHead){
    PNODE p = pHead->pNext;
    
    while(p != NULL){
        printf("%d   ", p->data);
        p = p->pNext;
    }
    
    printf("\n");
}