线性表综合实验（双链表）

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。

源代码：

#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>::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“霜降”的位置:" << demo.Locate("霜降") << endl;      cout << "-------------------------------------" << endl;      cout << "在第三与第四间插入“秋分”同学的成绩" << endl;      demo.Insert({ "秋分",95,86,93}, 5);      demo.PrintList();      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;  }