C++哈希錶鏈接錯誤

Question

由於某些原因，我的代碼運行不正常。它會進行編譯，但是當它進入輸出屏幕時，它只會顯示「發生錯誤」。它沒有列出任何種類的錯誤。我一直在嘗試在代碼中查找錯誤，但似乎無法找到它的位置。這裏是我的代碼：

class Node 
{ 
private: 
    int key; 
    int value; 
    Node* next; 
public: 
    Node(); 
    ~Node(); 
    void setKey(int num); 
    int getKey(); 
    void setValue(int x); 
    int getValue(); 
    void setNext(Node* theNext); 
    Node* getNext(); 
}; 

Node::Node() 
{ 
    next = NULL; 
} 

Node::~Node() 
{ 

} 

void Node::setKey(int num) 
{ 
    key = num; 
} 

int Node::getKey() 
{ 
    return key; 
} 

void Node::setValue(int x) 
{ 
     value = x; 
} 

int Node::getValue() 
{ 
    return value; 
} 

void Node::setNext(Node* theNext) 
{ 
    next = theNext; 
} 

Node* Node::getNext() 
{ 
    return next; 
} 

const int SIZE = 7; 

class chainTable 
{ 
private: 
    Node* data[SIZE]; 
public: 
    chainTable(); 
    ~chainTable(); 
    int chainHash(int num); 
    void insert(int key, int value); 
    void printTable(); 
}; 

chainTable::chainTable() 
{ 
    for (int i = 0; i < SIZE; i++) 
    { 
     data[i]->setValue(-1); 
    } 
} 

chainTable::~chainTable() 
{ 

} 

int chainTable::chainHash(int num) 
{ 
    return num % 5; 
} 

void chainTable::insert(int key, int value) 
{ 
    if (data[key]->getValue() == -1) 
    { 
     data[key] = new Node; 
     data[key]->setValue(value); 
     data[key]->setKey(key); 
     data[key]->setNext(NULL); 
    } 
    else 
    { 
     Node* temp = data[key]; 

     while (temp->getNext() != NULL) 
     { 
      temp = temp->getNext(); 
     } 

     Node* newEntry = new Node(); 
     newEntry = temp->getNext(); 

     newEntry->setKey(key); 
     newEntry->setValue(value); 
     newEntry->setNext(NULL);   
    } 
} 

void chainTable::printTable() 
{ 
    for (int i = 0; i < SIZE; i++) 
    { 
     Node* temp = data[i]; 

     while (temp->getNext()) 
     { 
      cout << temp->getValue(); 
     } 
    } 
} 

int main() 
{ 
    chainTable theChain; 

    int arr[7] = {1,2,5,7,7,9,1}; 

    for (int i = 0; i < 7; i++) 
    { 
     int arrHash = theChain.chainHash(arr[i]); 
     theChain.insert(arrHash,arr[i]); 
    } 

    return 0; 
} 

Answer 1

的錯誤是在構造函數和insert：沒有Node對象，所以value不能設置。我也改變了printTable。 我沒有嘗試它，但是這樣應該會更好：

class Node 
{ 
private: 
    int key; 
    int value; 
    Node* next; 
public: 
    Node(); 
    ~Node(); 
    void setKey(int num); 
    int getKey(); 
    void setValue(int x); 
    int getValue(); 
    void setNext(Node* theNext); 
    Node* getNext(); 
}; 

Node::Node() 
{ 
    next = NULL; 
} 

Node::~Node() 
{ 

} 

void Node::setKey(int num) 
{ 
    key = num; 
} 

int Node::getKey() 
{ 
    return key; 
} 

void Node::setValue(int x) 
{ 
     value = x; 
} 

int Node::getValue() 
{ 
    return value; 
} 

void Node::setNext(Node* theNext) 
{ 
    next = theNext; 
} 

Node* Node::getNext() 
{ 
    return next; 
} 

const int SIZE = 7; 

class chainTable 
{ 
private: 
    Node* data[SIZE]; 
public: 
    chainTable(); 
    ~chainTable(); 
    int chainHash(int num); 
    void insert(int key, int value); 
    void printTable(); 
}; 

chainTable::chainTable() 
{ 
    for (int i = 0; i < SIZE; i++) 
    { 
     //data[i]->setValue(-1); 
     data[i] = 0; 
    } 
} 

chainTable::~chainTable() 
{ 
    // ToDo: delete all nodes 
} 

int chainTable::chainHash(int num) 
{ 
    return num % 5; 
} 

void chainTable::insert(int key, int value) 
{ 
    if (data[key] == NULL) 
    { 
     data[key] = new Node; 
     data[key]->setValue(value); 
     data[key]->setKey(key); 
     data[key]->setNext(NULL); 
    } 
    else 
    { 
     Node* temp = data[key]; 

     while (temp->getNext() != NULL) 
     { 
      temp = temp->getNext(); 
     } 

     Node* newEntry = new Node(); 
     newEntry = temp->getNext(); 

     newEntry->setKey(key); 
     newEntry->setValue(value); 
     newEntry->setNext(NULL);   
    } 
} 

void chainTable::printTable() 
{ 
    for (int i = 0; i < SIZE; i++) 
    { 
     Node* temp = data[i]; 

     while (temp) 
     { 
      cout << temp->getValue(); 
      temp = temp->getNext(); 
     } 
    } 
} 

int main() 
{ 
    chainTable theChain; 

    int arr[7] = {1,2,5,7,7,9,1}; 

    for (int i = 0; i < 7; i++) 
    { 
     int arrHash = theChain.chainHash(arr[i]); 
     theChain.insert(arrHash,arr[i]); 
    } 

    return 0; 
}