请教一道题。这题是建立两个链表，再把它们连接起来，就是在第一条链表的结尾连接上第二条链表，下面是我写的程序，为什么打印出的数据少了两条链表的最后一个数据？
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#include<stdio.h>
#include<stdlib.h>

#define M 4
#define N 3
#define LEN sizeof(struct ListData)

struct ListData
{
int num;
struct ListData *next;
};

typedef struct ListData LIST;

int n;

struct ListData * __CreatList(int count)
{
n = 0;

struct ListData *head;
struct ListData *p1, *p2;

p1 = p2 = (struct ListData *)malloc(LEN);
if (p1 == NULL)
{
printf("Can't get values.\n");
exit (1);
}

head = NULL;

printf("Input the data:\n");
scanf("%d", &p1->num);

while (count)
{
n++;

if (n == 1)
head = p1;
else
p2->next = p1;

p2 = p1;

p1 = (struct ListData *)malloc(LEN);
if (NULL == p1)
{
exit (1);
}

printf("Input the data:\n");
scanf("%d", &p1->num); /*这里.你想想能接受到最后一个数字吗 */

count--;
}

p2->next = NULL;

return (head);
}

struct ListData *__LinkList(LIST *L1, LIST *L2)
{
struct ListData *P0, *head;

head = L1->next; /* head指向哪..你第一个结点不要了? */

while (L1)
{
P0 = L1;
L1 = L1->next;
}

P0->next = L2->next; /* 你把L2的第一个结点也给扔了 */

free(L2); /* 你这释放的是什么..再说.释放应该在打印里释放. */

return (head);
}

void __PrintList(struct ListData *P)
{
struct ListData *L;

L = P;

printf("Now the list_data is:\n");
if (P != NULL)
{
while (L != NULL)
{
printf("%d ", L->num);
L = L->next;
}
}
}

int main(void)
{
struct ListData *L1, *L2, *head;

L1 = __CreatList(M);
L2 = __CreatList(N);

head = __LinkList(L1, L2);

__PrintList(head);

system("Pause");
return 0;
}

struct ListData * __CreatList(int count)
{
n = 0;

struct ListData *head;
struct ListData *p1, *p2;

p1 = p2 = (struct ListData *)malloc(LEN);
if (p1 == NULL)
{
printf("Can't get values.\n");
exit (1);
}

head = NULL;

printf("Input the data:\n");
scanf("%d", &p1->num);

while (count) /* 你已经输入一次 而count没有减1 当然会多一次 */
{
n++;

if (n == 1)
head = p1;
else
p2->next = p1;

p2 = p1;

p1 = (struct ListData *)malloc(LEN);
if (NULL == p1)
{
exit (1);
}

printf("Input the data:\n");
scanf("%d", &p1->num);

count--;
}

p2->next = NULL;

return (head);
}