为什么无法输出插入后的链表

Question

问题遇到的现象和发生背景

问题相关代码，请勿粘贴截图

运行结果及报错内容

我的解答思路和尝试过的方法

我想要达到的结果

#include<stdio.h>
#include<stdlib.h>
struct node{
    int data;
    struct node *next;
};
struct node *creat(int a[],int n);
struct node *insert(struct node *head,int x);
void print(struct node *head);
int main()
{
    struct node *head=NULL;
    int a[10];
    int repeat,i,j,n,x;//x-待插入的数据 
    scanf("%d",&repeat);
    for(i=0;i<repeat;i++)
    {
        scanf("%d",&n);
        for(j=0;j<n;j++)    
        scanf("%d",&a[j]); 
        scanf("%d",&x);
        head=creat(a,n);
        insert(head,x);
        head=insert(head,x);
        printf("size=%d:",n+1);
        print(head);
        printf("\n");
    }
        return 0;    
}
struct node *creat(int a[],int n)
{
    int i;
    struct node *head=NULL,*end,*p;
    end=head;    
    for(i=0;i<n;i++)
    {
    p=(struct node*)malloc(sizeof(struct node));
    p->data=a[i];
    p->next=NULL;
    if(head==NULL)
        {
            head=p;
            end=head;
        }
    else
    {
        end->next=p;
        end=end->next;
    }
    }
    end->next=NULL;
    return head;
}
struct node *insert(struct node *head,int x)
{
    struct node *p1=head,*p2=head->next,*p3=NULL,*end=NULL;
    p3->data=x;
    p3->next=NULL;
    for(end=head;end->next!=NULL;end=end->next);//最后一个结点 
    if(p3->data<head->data)//插入点在头结点前 
    {
        p3->next=head;
        return p3;
    }
    else if(x>end->data)
    {
    end->next=p3;
    return head;
    }
    else//插入点在链表中间 
    {
        for(p1=head;p1!=NULL,p2!=end;p1=p1->next)
        {
            p2=p1->next;
            if(x>=p1->data&&x<=p2->data)
            {
                p1->next=p3;
                p3->next=p2;
            }
        }
        return head;
    }
}
void print(struct node *head)
{
    struct node *p;
    p=head;
    for(p=head;p!=NULL;p=p->next)
    {
        if(p==head)
        printf("%d",p->data);
        else 
        printf(" %d",p->data);
    }
}

Answer 1

修改处见注释，供参考：

#include<stdio.h>
#include<stdlib.h>
struct node{
    int    data;
    struct node *next;
};
struct node *creat(int a[],int n);
struct node *insert(struct node *head,int x);
void print(struct node *head);
int main()
{
    struct node *head=NULL;
    int a[10];
    int repeat,i,j,n,x;//x-待插入的数据
    scanf("%d",&repeat);
    for(i=0;i<repeat;i++)
    {
        scanf("%d",&n);
        for(j=0;j<n;j++)
            scanf("%d",&a[j]);

        head=creat(a,n);
        print(head);   //修改
        printf("\n");  //修改

        scanf("%d",&x);
           //insert(head,x);//修改
        head=insert(head,x);
        printf("size=%d:",n+1);
        print(head);
        printf("\n");
    }
    system("pause");
    return 0;
}
struct node *creat(int a[],int n)
{
    int i;
    struct node *head=NULL,*end,*p;
    end=head;
    for(i=0;i<n;i++)
    {
        p=(struct node*)malloc(sizeof(struct node));
        p->data=a[i];
        p->next=NULL;
        if(head==NULL)
        {
            head=p;
            end=head;
        }
        else
        {
            end->next=p;
            end=end->next;
        }
    }
    end->next=NULL;
    return head;
}
struct node *insert(struct node *head,int x)
{
    struct node *p1=head,*p2=NULL,*p3=NULL; //,*end=NULL;//修改

    p3 = (struct node*)malloc(sizeof(struct node)); //修改
    p3->data=x;
    p3->next=NULL;

    //for(end=head;end->next!=NULL;end=end->next);//最后一个结点//修改
    while (p1){
          if(p3->data < p1->data)//插入点在头结点前 if(p3->data<head->data)//修改
          {
               if (p1 == head){   //p3->next=head; //修改
                   p3->next = head;//return p3;  //修改
                   head = p3;
               }
               else{                           //修改
                   p3->next = p2->next;        //修改
                   p2->next = p3;              //修改
               }
               return head;                    //修改
          }
               //else if(x>end->data)         //修改
               //{
               //     end->next=p3;
               //     return head;
               //}
          else //插入点在链表中间
          {
               // for(p1=head;p1!=NULL,p2!=end;p1=p1->next) //修改
               //{
               //  p2=p1->next;
               //if(x>=p1->data&&x<=p2->data)
               // {
               // p1->next=p3;
               // p3->next=p2;
               p2 = p1;      //修改
               p1 = p1->next;//修改
          }
    }
    if (p1 == NULL)   //修改
        p2->next = p3;//修改
    return head;
}
void print(struct node *head)
{
    struct node *p;
    p=head;
    for(p=head;p!=NULL;p=p->next)
    {
        if(p==head)
           printf("%d",p->data);
        else
           printf(" %d",p->data);
    }
}