-2
我有一個程序，我試圖做一個單鏈表和它的副本構造函數。該程序編譯成功;然而，在運行時，它會打印它應該輸出的一半，然後在沒有打印剩餘輸出的情況下崩潰（對於不好的技術詞彙抱歉）。重載構造函數不能用於單鏈表
我有一種感覺，我的List類中的拷貝構造函數有問題，因爲程序崩潰，因爲它到達了那一點。
這裏是我的代碼：
# include<iostream>
using namespace std;
class Node
{
public:
int value;
Node* next;
};
class List
{
public:
List();
List(const List &other){
head = new Node;
head = NULL;
Node* temp7;
temp7 = head;
Node* temp6 = other.head;
while (temp6 != NULL)
{
temp7 = new Node;
temp7->value = temp6->value;
temp7 = temp6;
temp6 = temp6->next;
}
}
void push_front(int value){
temporary = new Node;
temporary->value = value;
temporary->next = NULL;
temporary->next = head;
head = temporary;
}
void insert_at(int index, int value){
Node* temp4 = new Node;
temp4->value = value;
temp4->next = NULL;
if (index == 1)
{
temp4->next = head;
head = temp4;
return;
}
Node* temp5 = head;
for (int k = 0; k < index - 2; k++)
temp5 = temp5->next;
temp4->next = temp5->next;
temp5->next = temp4;
}
void remove_at(int index){
Node* temp2 = head;
if (index == 1)
{
head = temp2->next;
delete temp2;
return;
}
for (int j = 0; j < index - 2; j++)
temp2 = temp2->next;
Node* temp3 = temp2->next;
temp2->next = temp3->next;
delete temp3;
}
string printList(void);
private:
Node* head;
Node* temporary;
};
List::List(){
head = NULL;
}
string List::printList(void)
{
Node* temp1 = head;
int counting = 0;
while (temp1 != NULL)
{
cout << "list[" << counting << "] == " << temp1->value << endl;
temp1 = temp1->next;
counting++;
}
}
int main()
{
List list1;
list1.push_front(4);
list1.push_front(3);
list1.push_front(2);
list1.push_front(1);
cout << "list1" << endl;
list1.printList();
cout << endl;
List list2(list1);
cout << "list2" << endl;
list2.printList();
cout << endl;
list1.insert_at(1, 6);
list2.remove_at(2);
cout << "list1" << endl;
list1.printList();
cout << endl;
cout << "list2" << endl;
list2.printList();
cout << endl;
return 0;
}
我無法找出錯誤的在節目源。任何人都可以請建議解決方案？
僅供參考，輸出應該是這樣的：（程序只輸出崩潰前的前5行）。
>list1
>
>list[0] == 1
>
>list[1] == 2
>
>list[2] == 3
>
>list[3] == 4
>
>list2
>
>list[0] == 1
>
>list[1] == 2
>
>list[2] == 3
>
>list[3] == 4
>
>list1
>
>list[0] == 1
>
>list[1] == 6
>
>list[2] == 2
>
>list[3] == 3
>
>list[4] == 4
>
>list2
>
>list[0] == 1
>
>list[1] == 2
>
>list[2] == 4
順便說一句，這是我對堆棧溢出的第一個問題，所以如果有什麼錯了或什麼我應該做的事情，請不要猶豫，指正。
非常感謝您的幫助大家:)
***我解決了這一問題。顯然，我沒有正確地實現拷貝構造函數。反正感謝您的所有意見和建議:-)
//包含標準文件 的#include
// Use standard namespace
using namespace std;
// Declare node class
class Node
{
// All values are public; value of node, and next node pointer
public:
int value;
Node* next;
};
// Declare singly linked list class
class List
{
public:
// Declare main constructor
// Declare copy constructor
List();
List(const List ©ing) : head(NULL)
{
// Use a node to move through the source linked list
// Set the size of the new linked list
// For every node in old list, copy it to a new node and link it to the new singly linked list
Node* cur = copying.head;
int size = copying.size();
Node* end = NULL;
for(int q = 0; q < size; q++)
{
Node* n = new Node;
n->value = cur->value;
if (head == NULL)
{
head = n;
end = head;
}
else
{
end->next = n;
end = n;
}
cur = cur->next;
}
end->next = NULL;
}
// Push front a new node
// Add its value and set its next pointer to NULL
void push_front(int value){
temporary = new Node;
temporary->value = value;
temporary->next = NULL;
temporary->next = head;
head = temporary;
}
// Insert node between x and x+1
// Get the new node's value
// Create the new node by moving from the head->next method
// Add the value and set up the node
void insert_at(int index, int value){
Node* temp4 = new Node;
temp4->value = value;
temp4->next = NULL;
if (index == 1)
{
Node* temp9 = head->next;
temp4->next = temp9;
head->next = temp4;
return;
}
Node* temp5 = head;
for (int k = 0; k < index - 2; k++)
temp5 = temp5->next;
temp4->next = temp5->next;
temp5->next = temp4;
}
// Remove node number [index]
// Get the head
// Iterate through the linked list
// When at the node before the one that has to be deleted, set its value to the node after the next one
// Delete the node that should be deleted
void remove_at(int index){
Node* temp2 = head;
if (index == 1)
{
head = temp2->next;
delete temp2;
return;
}
for (int j = 0; j < index - 1; j++)
temp2 = temp2->next;
Node* temp3 = temp2->next;
temp2->next = temp3->next;
delete temp3;
}
// Simple function to pass the head of a singly linked list
// Simple function to get the size of a function
Node * PassHead(void);
int size()const;
private:
Node* head;
Node* temporary;
};
// Returns head
Node * List::PassHead()
{
return head;
}
// Constructor sets head to NULL
List::List(){
head = NULL;
}
// Gets the size of the singly linked list.
// While the node_>next is not NULL, add 1 to counter
// return counter
int List::size()const {
Node* temp1 = head;
int counting = 0;
while (temp1 != NULL)
{
counting++;
temp1 = temp1->next;
}
return counting;
}
// Same function as the size() function, excetp this time, print the node value while iterating through list
// Nothing returned
void printList(List object)
{
Node* temp1 = object.PassHead();
int counting = 0;
while (temp1 != NULL)
{
cout << "list[" << counting << "] == " << temp1->value << endl;
temp1 = temp1->next;
counting++;
}
}
// Declare main function here
int main()
{
// Object of List
List list1;
// Push some values
list1.push_front(4);
list1.push_front(3);
list1.push_front(2);
list1.push_front(1);
// Print the first list
cout << "list1" << endl;
printList(list1);
cout << endl;
// Copy constructor for second list
List list2(list1);
// Print second list
cout << "list2" << endl;
printList(list2);
cout << endl;
// Insert node in first list
list1.insert_at(1, 6);
// Remove node in second list
list2.remove_at(2);
// Print first list
cout << "list1" << endl;
printList(list1);
cout << endl;
// Print second list
cout << "list2" << endl;
printList(list2);
cout << endl;
// Program ran successfully
return 1;
}
你在你的拷貝構造函數中忘記了一個'}'。 – Rakete1111
您應該包含** complete **錯誤消息。它們通常包含一個行號，這對於發現問題很有幫助。 –
謝謝@ Rakete1111！我錯過了那個障礙。但是，即使在添加之後，它仍然不起作用。 –