所以我以为我理解如何实现指针数组，但我的编译器说否则 =(。任何帮助将不胜感激，我觉得我已经很接近了，但缺少一些关键的东西。
1.) 我声明了一个名为 node 的结构：。
struct node {
int num;
node *next;
}
2.) 我已经声明了一个指向指针数组的指针，如下所示：
node **arrayOfPointers;
3.)然后我通过这样做动态创建了指针数组：
arrayOfPointers = new node*[arraySize];
我的理解是，arrayOfPointers 现在指向 x 节点类型的数组，其中 x = arraySize。
4.) 但是当我想访问 arrayOfPointers 中的第五个元素以检查其下一个指针是否为空时，我收到了分段错误错误。使用这个：
if (arrayOfPointers[5]->next == NULL)
{
cout << "I'm null" << endl;
}
有谁知道为什么会发生这种情况？我可以通过以下操作为 num 赋值： arrayOfPointers[5]->num = 77;
但我很困惑为什么检查结构中的指针会导致错误。另外，当我们这样做时，将 arrayOfPointers 传递到函数中的正确原型是什么？它仍然是 (node **arrayOfPointers) 还是其他类似 (node * &arrayOfPointers) 的东西？
预先感谢您提供的任何提示或指示（哈哈）！
完整代码（已更新）：
/*
* Functions related to separate chain hashing
*/
struct chainNode
{
int value;
chainNode *next;
};
chainNode* CreateNewChainNode (int keyValue)
{
chainNode *newNode;
newNode = new (nothrow) chainNode;
newNode->value = keyValue;
newNode->next = NULL;
return newNode;
}
void InitDynamicArrayList (int tableSize, chainNode **chainListArray)
{
// create dynamic array of pointers
chainListArray = new (nothrow) chainNode*[tableSize];
// allocate each pointer in array
for (int i=0; i < tableSize; i++)
{
chainListArray[i]= CreateNewChainNode(0);
}
return;
}
bool SeparateChainInsert (int keyValue, int hashAddress, chainNode **chainListArray)
{
bool isInserted = false;
chainNode *newNode;
newNode = CreateNewChainNode(keyValue); // create new node
// if memory allocation did not fail, insert new node into hash table
if (newNode != NULL)
{
//if array cell at hash address is empty
if (chainListArray[hashAddress]->next == NULL)
{
// insert new node to front of list, keeping next pointer still set to NULL
chainListArray[hashAddress]->next = newNode;
}
else //else cell is pointing to a list of nodes already
{
// new node's next pointer will point to former front of linked list
newNode->next = chainListArray[hashAddress]->next;
// insert new node to front of list
chainListArray[hashAddress]->next = newNode;
}
isInserted = true;
cout << keyValue << " inserted into chainListArray at index " << hashAddress << endl;
}
return isInserted;
}
/*
* Functions to fill array with random numbers for hashing
*/
void FillNumArray (int randomArray[])
{
int i = 0; // counter for for loop
int randomNum = 0; // randomly generated number
for (i = 0; i < ARRAY_SIZE; i++) // do this for entire array
{
randomNum = GenerateRandomNum(); // get a random number
while(!IsUniqueNum(randomNum, randomArray)) // loops until random number is unique
{
randomNum = GenerateRandomNum();
}
randomArray[i] = randomNum; // insert random number into array
}
return;
}
int GenerateRandomNum ()
{
int num = 0; // randomly generated number
// generate random number between start and end ranges
num = (rand() % END_RANGE) + START_RANGE;
return num;
}
bool IsUniqueNum (int num, int randomArray[])
{
bool isUnique = true; // indicates if number is unique and NOT in array
int index = 0; // array index
//loop until end of array or a zero is found
//(since array elements were initialized to zero)
while ((index < ARRAY_SIZE) && (!randomArray[index] == 0))
{
// if a value in the array matches the num passed in, num is not unique
if (randomArray[index] == num)
{
isUnique = false;
}
index++; // increment index counter
} // end while
return isUnique;
}
/*
*main
*/
int main (int argc, char* argv[])
{
int randomNums[ARRAY_SIZE] = {0}; // initialize array elements to 0
int hashTableSize = 0; // size of hash table to use
chainNode **chainListArray;
bool chainEntry = true; //testing chain hashing
//initialize random seed
srand((unsigned)time(NULL));
FillNumArray(randomNums); // fill randomNums array with random numbers
//test print array
for(int i = 0; i < ARRAY_SIZE; i++)
{
cout << randomNums[i] << endl;
}
//test chain hashing insert
hashTableSize = 19;
int hashAddress = 0;
InitDynamicArrayList(hashTableSize, chainListArray);
//try to hash into hash table
for (int i = 0; i < ARRAY_SIZE; i++)
{
hashAddress = randomNums[i] % hashTableSize;
chainEntry = SeparateChainInsert(randomNums[i], hashAddress, chainListArray);
}
system("pause");
return 0;
}
