双链表的基本使用及其应用(实验2.2)

一．实验目的

  巩固线性表的数据结构的存储方法和相关操作，学会针对具体应用，使用线性表的相关知识来解决具体问题。

二.实验内容

1.建立一个由n个学生成绩的顺序表，n的大小由自己确定，每一个学生的成绩信息由自己确定，实现数据的对表进行插入、删除、查找等操作。分别输出结果。
#include <iostream>
#include<string>
using namespace std;

struct Student
{
string name;
int Chinese;
int Math;
int English;
int Sum;

};
ostream& operator << (ostream& os, const Student &ob)
{
os << ob.name << "\t";
os << ob.Chinese << "\t";
os << ob.Math << "\t";
os << ob.English << "\t";
os << ob.Sum << "\t";
return os;
}
template <class DataType>
struct Node
{
DataType data;
Node<DataType> *prior, *next;
};

template <class DataType>
class DoubleLink
{
public:
DoubleLink();
DoubleLink(DataType a[], int n);
~DoubleLink();
int Length();
DataType Get(int i);
int Locate(string x);
void Insert(DataType x, int i);
DataType Delete(int i);
void PrintList();

private:
Node<DataType> * first; // 定义头指针
Node<DataType> * last; // 定义尾指针
int length;

};

template <class DataType>
void DoubleLink<DataType> ::PrintList()
{
Node<DataType>*p;
p = first->next; //工作指针P初始化
cout << "-------------------------------------" << endl;
cout << "姓名" << "\t" << "语文" << "\t" << "数学" << "\t" << "英语" << "\t" << "总分" << "\t" << endl;
for (int i = 0; i < length; i++)
{
cout << p->data << endl;
p = p->next;
}
cout << "-------------------------------------" << endl;

}

template <class DataType>
int DoubleLink<DataType>::Length()
{
return length;
}
template <class DataType>
DataType DoubleLink<DataType>::Get(int i)
{
Node<DataType>*p = NULL;
p = first->next;
int count = 1;
while (p != NULL&&count<i)
{
p = p->next;
count++;
}
if (p == first) throw"输入位置异常";
else
{
return p->data;
}
}

template <class DataType>
int DoubleLink<DataType>::Locate(string x)
{
Node<Student>*p = NULL;
p = first->next;
int count = 1;
while (p != first)
{
if (p->data.name == x)
return count;
p = p->next;
count++;
}

return 0;
}

template <class DataType>
void DoubleLink<DataType>::Insert(DataType x, int i)
{
Node<DataType>*p, *s;
p = first->next;
int count = 1;
while (p != first && count < i - 1)
{
p = p->next;
count++;
}
if (p == first)throw "插入位置异常";
else
{
s = new Node<DataType>;
s->data = x;
s->prior = p;
s->next = p->next;
(p->next)->prior = s;
p->next = s;
s->data.Sum = s->data.Chinese + s->data.Math + s->data.English;
length++;
}

}

template <class DataType>
DoubleLink <DataType&
4000
gt;::DoubleLink()
{
first = new Node<DataType>;
first->next = first;
length = 0;
}

template <class DataType>
DoubleLink<DataType>::DoubleLink(DataType a[], int n) //尾插法
{
Node<DataType> *s; //s为工作指针
first = new Node<DataType>;
first->prior = last;
last = first; //尾指针初始化
for (int i = 0; i < n; i++)
{
s = new Node<DataType>; //为每个数组元素建立一个结点
s->data = a[i];
s->prior = last;
last->next = s; //将结点s插入到终端结点之后
last = s;
length++;
}
last->next = first; //链接建立完毕，将终端结点的指针域指向头指针
}

template <class DataType>
DataType DoubleLink<DataType>::Delete(int i)
{
Node<DataType>*p; //工作指针初始化
p = first->next;
int count = 0;
while (p != first&&count < i - 1)
{
p = p->next;
count++;
}
if (p == first || p->next == NULL)
throw "删除位置异常";
else
{
DataType x = p->data;
(p->prior)->next = p->next;
(p->next)->prior = p->prior;
delete p;
length--;
return x;
}

}

template <class DataType>
DoubleLink <DataType>::~DoubleLink()
{
Node<DataType>*p = first; //工作结点p初始化

for (int i = 0; i < length; i++)
{
p = first;
first = first->next;
delete p;
}
length = 0;
cout << "链表已成功删除。" << endl;

}
int main()
{

Student stu[100]; //最大容纳量
int num;
string TempName;
cout << "请输入学生人数：";
cin >> num;

for (int i = 0; i < num; i++)
{
cout << "输入“break”退出输入" << endl;
cout << "请输入第" << i + 1 << "名学生姓名:";
cin >> TempName;
if (TempName == "break")
{
num = i;
break;

}
stu[i].name = TempName;
cout << "请输入第" << i + 1 << "名学生语文成绩:";
cin >> stu[i].Chinese;
cout << "请输入第" << i + 1 << "名学生数学成绩:";
cin >> stu[i].Math;
cout << "请输入第" << i + 1 << "名学生英语成绩:";
cin >> stu[i].English;
stu[i].Sum = stu[i].Chinese + stu[i].Math + stu[i].English;
cout << "-------------------------------------" << endl;
}

DoubleLink<Student> demo(stu, num);
demo.PrintList();
cout << "链表总长为：";
cout << demo.Length()<<endl;
cout << "-------------------------------------" << endl;

cout << "查找第三名学生成绩:" << endl;
cout << "-------------------------------------" << endl;
cout << "姓名" << "\t" << "语文" << "\t" << "数学" << "\t" << "英语" << "\t" << "总分" << "\t" << endl;
cout << demo.Get(3) << endl;
cout << "-------------------------------------" << endl;

cout << "查找姓名为“小明”的位置:" << demo.Locate("xx") << endl;
cout << "-------------------------------------" << endl;

cout << "在第三与第四间插入“小叶”同学的成绩" << endl;
cout << "链表总长为：";
cout << demo.Length()<<endl;
cout << "-------------------------------------" << endl;
cout << "删除第2位同学的成绩" << endl;
demo.Delete(2);
demo.PrintList();
return 0;
}

三、实验心得：

通过本次实验，我基本掌握了双链表的基本操作。链表的内涵并非像数组、类、结构体、联合体等那样，链表不是C++语言中的关键词，链表是我们利用C++语言中的基本数据类型构造出来的结构，具有动态申请内存和增删效率高的特点。