小白初学编程，大佬们可以帮忙看看这个合并有序数组的代码错在哪吗？

Question

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

typedef struct ListNODE
{
	int date;
	struct ListNODE * pNext;
	
}LNODE , *PLNODE;

PLNODE creat(void);
void traverse_LIST(PLNODE pHead);
PLNODE combine(PLNODE pHead1, PLNODE pHead2);

int main(void)
{
	PLNODE pHead1 = NULL;
	pHead1 = creat();
	PLNODE pHead2 = NULL;
	pHead2 = creat();
	PLNODE p =combine(pHead1 , pHead2);
	traverse_LIST(p);
	return 0;
}

PLNODE creat(void)
{
	int len;
	int i;
	int val;
	PLNODE pHead = (PLNODE)malloc(sizeof(LNODE));
	if (NULL == pHead)
	{
		printf("分配失败，程序终止！\n");
			exit(-1);
	}
	PLNODE pTail = pHead;
	pTail->pNext = NULL;
	if (NULL == pHead)
	{
		printf("分配失败，程序终止！\n");
			exit(-1);
	}
	printf("请输入数组长度len=");
	scanf("%d", &len);

	printf("请输入数组元素:");
	for (i = 0; i < len; i++)
	{
		PLNODE pNew = (PLNODE)malloc(sizeof(LNODE));
		scanf("%d", &val);
		pNew->date = val;
		pTail->pNext = pNew;
		pNew->pNext = NULL;
		pTail = pNew;
	}
	
	return pHead;
}

void traverse_LIST(PLNODE pHead)
{
	PLNODE p = pHead->pNext;
	while (NULL != p)
	{
		printf("%d\n", p->date);
		p = p->pNext;
	}

}

PLNODE combine(PLNODE pHead1, PLNODE pHead2)
{
	PLNODE p = (PLNODE)malloc(sizeof(LNODE));
	PLNODE pTail = p;
	while (pHead1 != NULL || pHead2 != NULL)
	{
		if (pHead1 != NULL && pHead2 != NULL)
		{
			if (pHead1->date > pHead2->date)
			{
				pTail->pNext = pHead2;
				pTail = pHead2;
				pHead2 = pHead2->pNext;
			}
			else
			{
				pTail->pNext = pHead1;
				pTail = pHead1;
				pHead1 = pHead1->pNext;
			}
		}
		else if (pHead1 != NULL)
		{
			pTail->pNext = pHead1;
			pTail = pHead1;
			pHead1 = pHead1->pNext;
		}
		else if (pHead2 != NULL)
		{
			pTail->pNext = pHead2;
			pTail = pHead2;
			pHead2 = pHead2->pNext;
		}
	}
	return p->pNext->pNext;
}

这是在vs上的运行结果

这是在cb上的运行结果

为什么这两个结果会不一样呢？

谢谢大佬的解答！！！

Answer 1

你的代码中，创建链表和遍历链表的函数应该都工作正常。主要的问题出现在你的 combine 函数中，你在该函数中将 pHead1 和 pHead2 直接设置为要合并的链表的头，然后在进行排序合并时直接修改了这两个链表，这种情况下，你实际上是在修改原始链表，而不是创建一个新的合并后的链表。

为了解决这个问题，你应该在开始排序合并前，首先将 pHead1 和 pHead2 后移一位，以跳过空的头节点。你可以通过修改 combine 函数来实现：

PLNODE combine(PLNODE pHead1, PLNODE pHead2)
{
    PLNODE p = (PLNODE)malloc(sizeof(LNODE));
    PLNODE pTail = p;
    pHead1 = pHead1->pNext;  // Start from the first node
    pHead2 = pHead2->pNext;  // Start from the first node
    while (pHead1 != NULL || pHead2 != NULL)
    {
        if (pHead1 != NULL && pHead2 != NULL)
        {
            if (pHead1->date > pHead2->date)
            {
                pTail->pNext = pHead2;
                pTail = pHead2;
                pHead2 = pHead2->pNext;
            }
            else
            {
                pTail->pNext = pHead1;
                pTail = pHead1;
                pHead1 = pHead1->pNext;
            }
        }
        else if (pHead1 != NULL)
        {
            pTail->pNext = pHead1;
            pTail = pHead1;
            pHead1 = pHead1->pNext;
        }
        else if (pHead2 != NULL)
        {
            pTail->pNext = pHead2;
            pTail = pHead2;
            pHead2 = pHead2->pNext;
        }
    }
    return p->pNext;
}

这样做之后，你的 combine 函数应该就可以正确地工作了。最后，记得在代码中释放所有的动态分配的内存，以避