我是链接列表的新手,现在我遇到了如何将节点添加到列表中间的问题。例如,如果我在下面显示了一个名单,当我逐个添加数据时,就像下面的序列一样:
1.andrew
2.eric
3.madness
4.gerik
我想要我的数据" gerik "在" 疯狂"当它显示出来的地方。我能够对" eric "的数据进行排序。但是" eric "我不知道。我想要我的输出如下:
1.andrew
2.eric
3.gerik
4.madness
以下是我的示例代码,请通过给我建议或代码示例帮助我:
#include <iostream>
#include <string>
#include <cstdlib>
#include <cstring>
using namespace std;
struct node
{
char f_name[20];
char l_name[20];
char u_id[10];
node *next;
};
node *head;
node *curr;
//prototype
void display();
void add();
void search_name();
void insert_data(node *tempnode);
void insert_before_head(node *tempnode);
void menu(char choice);
char pause;
//function start...
void search_name()
{
char name[20];
curr = head;
cin.ignore(30,'\n');
cout<<"Key In Last Name :"<<endl;
cin.get(name, 20);
cin.ignore(30,'\n');
while((curr->next != NULL) && (strcmp(curr->l_name, name) != 0))
{
curr = curr->next;
}
if(curr != NULL)
{
cout<<"Record Found !"<<endl;
cout<<"First Name"<<setw(16)<<"Last Name"<<setw(16)<<"User ID"<<endl;
cout<<"--------------------------------------------------------------"<<endl;
cout<<curr->f_name<<setw(20)<<curr->l_name<<setw(16)<<curr->u_id<<endl<<endl;
}
else
{
cout<<"No Match !"<<endl;
cout<<"Press 'Enter' To Continue"<<endl;
cin.get(pause = getch());
system("cls");
}
};
void display()
{
curr = head;
if(head != NULL)
{
cout<<"First Name"<<setw(16)<<"Last Name"<<setw(16)<<"User ID"<<endl;
cout<<"--------------------------------------------------------------"<<endl;
while(curr != NULL)
{
cout<<curr->f_name<<setw(20)<<curr->l_name<<setw(16)<<curr->u_id<<endl;
curr = curr->next;
}
}
else
{
cout<<"No Data. File storage Empty!"<<endl;
}
};
void add()
{
node *temp;
temp = new node;
cin.ignore(30, '\n');
cout<<"Key In First Name:"<<endl;
cin.get(temp->f_name, 20);
cin.ignore(30, '\n');
cout<<"Key In Last Name:"<<endl;
cin.get(temp->l_name, 20);
cin.ignore(30, '\n');
cout<<"Key In Your ID:"<<endl;
cin.get(temp->u_id, 10);
insert_data(temp);
};
void insert_data(node *tempnode)
{
node *temp;
if(head == NULL)
{
node *temp;
temp = new node;
temp = head;
tempnode->next = NULL;
head = tempnode;
}
else if(strcmp(tempnode->l_name, head->l_name) < 0)
{
insert_before_head(tempnode);
}
else
{
temp = new node;
curr = head;
while(curr->next != NULL)
{
curr = curr->next;
}
temp = tempnode;
curr->next = tempnode;
tempnode->next = NULL;
}
};
void insert_before_head(node *tempnode)
{
node *temp;
if(head != NULL)
{
temp = new node;
temp = tempnode;
tempnode->next = head;
head = tempnode;
}
};
void menu(int choice)
{
switch (choice)
{
case 1 :
add();
break;
case 2:
display();
break;
case 3:
search_name();
break;
case 4:
cout<<"Exit Program !"<<endl;
break;
default :
cout<<"Error! Program Terminate !"<<endl;
}
};
int main()
{
int choice;
node *temp;
head = NULL;
curr = NULL;
cout << "Data Stack Head And Any Position !" << endl;
system("cls");
do{
cout<<"1. Add Data."<<endl;
cout<<"2. Show Data. "<<endl;
cout<<"3. Search Last Name "<<endl;
cout<<"4. Exit. "<<endl;
cin >>choice;
menu(choice);
}while(choice != 4);
return 0;
}
答案 0 :(得分:1)
要对链接列表进行排序,您需要使用具有合并排序的分而治之策略。
为了在中间插入,您需要创建2个节点Node slow和Node fast。首先,Node slow是head.next,Node fast是head.next.next,你继续通过slow = slow.next和fast = fast.next.next来移动那些2,直到你用Node快速结束。如果你考虑一下,fast的移动速度会比Node慢两倍,所以最后Node慢速将在中间。然后在该节点之后插入。
答案 1 :(得分:0)
我们想在列表newNode
中插入
让节点X
成为节点,之后应插入newNode
以保留排序顺序。
您可以在我的示例中重写insert_data(...)
功能。
我拿了代码,由WhozCraug吸收并重写它更明显。
void insert_data(node *newNode)
{
node **pointerToTheNextPtr = &head;
// find position to insert new node
while (*pointerToTheNextPtr && strcmp((*pointerToTheNextPtr)->l_name, newNode->l_name) < 0)
pointerToTheNextPtr = &((*pointerToTheNextPtr)->next);
// here pointerToTheNextPtr stores the pointer to the X->next field
// insert new node between X and *(X->next)
newNode->next = *pointerToTheNextPtr; // set newNode->next = X->next
*pointerToTheNextPtr = newNode; // set X->next = newNode
}