用链表存数据，为什么运行之后什么都没有

Question

#include
#include
typedef struct node{
int data;
struct node *next;
}*sqlist;//定义链表结构

sqlist creatlist(int n){//创建单向链表
sqlist head,p,q;
head=p=(sqlist)malloc(sizeof(node));
for(int i=0;i q=(sqlist)malloc(sizeof(node));
q->data=i;
p->next=q;
p=q;
}
p->next=NULL;
return head;
}

void printlist(sqlist head){// 创建单向非循环链表
sqlist p=head->next;
while(p!=NULL){
printf("%d",p->data);
p=p->next;}
printf("\n");
}

void freelist(sqlist head){//释放链表
sqlist p,q;
p=head;
q=p->next;
while(q!=NULL){
q=p;
q=q->next;
free(p);}
free(head);
}

int main(){
int n;
sqlist head;
scanf("%d",&n);
head=creatlist(5);
printlist(head);
freelist(head);
return 0;
}

Answer 1

创建单项链表for循环有问题
修改了下

sqlist creatlist(int n)//尾插法创建有头结点的单向链表
{
    sqlist head, p, q;
    head = (sqlist)malloc(sizeof(struct node));
    p = head;
    for(int i = 0;i < n; i++)
    {
        q = (sqlist)malloc(sizeof(struct node));
        q->data = i;
        p->next = q;
        p = q;
    }
    p->next=NULL;
    return head;
}

还有就是释放内存那

void freelist(sqlist head)
{//释放链表
    sqlist p,q;
    p = head;
    while(q!=NULL)
    {
        p = q;
        q = p->next;
        free(p);
    }
}