创建链表，然后原地逆转，最后编历，不知道哪里错了

Question

#include<stdio.h>

#include<malloc.h>

#include<string.h>

#include<stdlib.h>

typedef struct Node

{

int data;

struct Node *pnext;

}Node,*pNode;

pNode createlist()

{

int len = 5, i = 0;

pNode head,q;

head = (pNode)malloc(sizeof(Node));

q = head;

head->pnext=NULL;

for(i = 0; i < len; i++)

{

pNode p;

p = (pNode)malloc(sizeof(Node));

p->pnext=NULL;

if(p != NULL)

{

printf("succeed\n");

printf("请输入第%d个节点的数据", i+1);

scanf("%d",&p->data);

q->pnext=p;

// p->pnext = NULL;

q=p;

}

else

{

printf("fail\n");

exit(-1);

}

}

return head;

}

pNode change(pNode head)

{

pNode p, q, r;

p = head;

q = NULL;

while(p)

{

r = p->pnext;

p->pnext = q;

q = p;

p = r;

}

return r;

}

void travers(pNode head)

{

pNode p=head->pnext;

while(p != NULL)

{

printf("%d",p->data);

p = p->pnext;

}

return;

}

int main()

{

pNode head;

head = createlist();

head = change(head);

travers(head);

return 0;

}