我正在尝试从双向链表的末尾删除一个节点,但我得到:
分段错误
我添加了不同的函数来添加节点,从开始,从结束,到任何位置。我检查了节点的插入,它工作正常,DLL显示正确,但是当涉及到删除功能时,它给出了分段错误。
struct Node {
Node* left;
Node* right;
int data;
};
Node* head = NULL;
void insertion_At_End(int element) {
Node* ptr = head;
Node* temp = new Node;
temp->left = temp->right = NULL;
temp->data = element;
if(head==NULL) {
head = temp;
} else {
while(ptr->right!=NULL) {
ptr = ptr->right;
}
temp->left = ptr->right;
ptr->right = temp;
}
}
void insertion_At_Beg(int element) {
Node* ptr = head;
Node* temp = new Node;
temp->left = temp->right = NULL;
temp->data = element;
if(head==NULL) {
head = temp;
} else {
temp->right = ptr;
ptr->left = temp;
head = temp;
}
}
void insertion_At_Pos(int element , int position , int length) {
Node* ptr;
Node* temp = new Node;
temp->left = temp->right = NULL;
temp->data = element;
int counter = 1;
if(position==1) {
insertion_At_Beg(element);
}
else if(position==length) {
insertion_At_End(element);
}
else {
ptr = head;
while(counter!=(position-1)) {
ptr = ptr->right;
counter++;
}
temp->right = ptr->right;
ptr->right->left = temp;
temp->left = ptr;
ptr->right = temp;
}
}
void deletion_At_End() {
Node *ptr = head;
while(ptr->right!=NULL) {
ptr = ptr->right;
}
ptr->left->right=NULL;
delete ptr;
}
如果我列表中只有一个元素,我会收到错误。当列表中只有一个元素时,您无法设置它左侧指向 NULL 的内容,因为它不存在!这对我有用:
void deletion_At_End() {
Node *ptr = head;
while(ptr->right!=NULL) {
ptr = ptr->right;
}
if(ptr->left == NULL){
delete ptr;
}
else{
ptr->left->right=NULL;
delete ptr;
}
}