为什么下列子函数实现单链表 在指定位置插入元素，不能像下面这么做
MyListInsert里面没有开辟新的空间来存放新的节点，ListInsert里面重新开辟了空间来存放新的节点，为什么要开辟新的空间来存数据，没必要？我写的
int MyListInsert(Node* pHead, Node* pElem, int index)
{
Node* pCurrentNode = pHead;
Node* temp = NULL;
int length = ListLength2(pHead);
if (index > 0 && index <= length)
{
for (int i = 0; i < length; i++)
{
if (i + 1 == index)
{
temp = pCurrentNode->pNext;
pCurrentNode = pElem;
pElem->pNext = temp;
return 1;
break;
}
else
{
pCurrentNode = pCurrentNode->pNext;
}
}
}
else
{
printf("!!!!index out the range of the array\n");
return 0;
}
}
老师i写的：
int ListInsert(Node* pHead, Node* pElem, int index)
{
int length = ListLength2(pHead);
if (index < 0 || index > length)
{
return 0;
}
//开辟空间，你不能直接将传进来的节点内存直接插入链表,这里
Node* pNode = (Node*)malloc(sizeof(Node));
strcpy_s(pNode->name, pElem->name);
strcpy_s(pNode->phone, pElem->phone);
if (pNode == NULL)
{
return 0;
}
Node* pCurrentNode = pHead;
int count = 0;
Node* temp = NULL;
while (pCurrentNode != NULL)
{
if (count == index)
{
temp = pCurrentNode->pNext;
pCurrentNode = pNode;
pNode->pNext = temp;
return 1;
}
count++;
pCurrentNode = pCurrentNode->pNext;
}
}
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