static void Main(string[] args)
{
Console.Title = "将学生按成绩从低到高排列";
StudentList students = new StudentList(20);
Console.WriteLine("排序前学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", students[i].Number, students[i].Name, students[i].Result);
}
Student temp;
//将建堆后的根结点与索引为i的结点交换
for (int i = 19; i >=1; i--)
{
CreateHeap(students, i);
temp = students[0];
students[0] = students[i];
students[i] = temp;
}
Console.ReadLine();
Console.Clear();
Console.WriteLine("排序后学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}",
students[i].Number, students[i].Name, students[i].Result);
}
Console.ReadLine();
}
static void Main(string[] args)
{
Console.Title = "查找指定姓名的学生信息";
Console.WriteLine("学生名单如下：");
StudentList students = new StudentList(20);
for (int i = 0; i < 20; i++)
{
Console.Write(students[i].Name + "\t");
if ((i + 1) % 5 == 0) Console.WriteLine();
}
string name;
do
{
Console.WriteLine("请输入要查询的学生姓名：");
name = Console.ReadLine();
int i = 0, count = 0;
//顺序查找学生指定学生信息
for (; i < 20; i++)
{
if (students[i].Name == name)
{
Console.WriteLine("学号：{0}\t年级：{1}\t成绩：{2}",
students[i].Number, students[i].Grade, students[i].Result);
count++;
}
}
if (count == 0) Console.WriteLine("无此学生信息！");
} while (name != string.Empty);
Console.ReadLine();
}
static void Main(string[] args)
{
Console.Title = "求学生成绩在前十名的学生";
StudentList students = new StudentList(20);
Console.WriteLine("排序前学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", students[i].Number, students[i].Name, students[i].Result);
}
Console.ReadLine();
Student temp;
int max = 0;
for (int i = 0; i < 10; i++)
{
max = i;
for (int j = i + 1; j < 20; j++)
{
if (students[j].Result > students[max].Result) max = j;//求成绩最好的学生索引
}
//将成绩最好的学生与索引i的学生交换
temp = students[i];
students[i] = students[max];
students[max] = temp;
}
Console.Clear();
Console.WriteLine("成绩排在前十名的学生信息表：");
for (int i = 0; i < 10; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", students[i].Number, students[i].Name, students[i].Result);
}
Console.ReadLine();
}
//将sts1[begin..end]归并排序为sts2[begin..end]
static void MergeSort(StudentList sts1, Student[] sts2, int begin, int end)
{
Student[] sts3 = new Student[sts1.Length];
if (begin == end)
sts2[begin] = sts1[begin]; //如果只有一个元素则直接将其归并到sts2中
else
{
int divide = (begin + end) / 2; //将表分割成两部分
MergeSort(sts1, sts3, begin, divide); //对左半部分进行归并排序并存储到sts3中
MergeSort(sts1, sts3, divide + 1, end); //对右半部分进行归并排序并存储到sts3中
Merge(sts3, sts2, begin, divide, end); //将左右两部分归并到sts2中
}
}
static void Main(string[] args)
{
Console.Title = "查询具有指定成绩的学生信息";
StudentList students = new StudentList(20);
Console.WriteLine("学生成绩单如下：");
for (int i = 0; i < 20; i++)
{
Console.Write(students[i].Result + "\t");
if ((i + 1) % 5 == 0) Console.WriteLine();
}
BTreeNode root = new BTreeNode(students[0]); //创建二叉排序树根结点
for (int i = 1; i < 20; i++)
{
CreateBinarySortingTree(root, students[i]); //根据学生成绩创建二叉排序树
}
int result;
//在二叉排序树上的查找指定成绩学生信息
do
{
Console.WriteLine("请输入要查询的学生的成绩：");
if (!int.TryParse(Console.ReadLine(), out result)) result = -1;
BTreeNode node = root;
bool successful = false;
while (node != null)
{
if (result > node.Student.Result) node = node.RightChild;//查找右子树
else if (result < node.Student.Result) node = node.LeftChild;//查找左子树
else//查找成功
{
Console.WriteLine("学号：{0}\t姓名：{1}\t年级：{2}",
node.Student.Number, node.Student.Name, node.Student.Grade);
successful = true;
break;
}
}
if (!successful) Console.WriteLine("无此学生信息！");//查找失败
} while (result != -1);
Console.ReadLine();
}
static void Main(string[] args)
{
Console.Title = "按学生成绩构造哈希表";
StudentList students = new StudentList(20);
Console.WriteLine("学生成绩单如下：");
for (int i = 0; i < 20; i++)
{
Console.Write(students[i].Result + "\t");
if ((i + 1) % 5 == 0) Console.WriteLine();
}
//创建哈希表
StudentNode[] hashTable = new StudentNode[5];
for (int i = 0; i < 20; i++)
{
int index = students[i].Result % 5; //计算哈希地址
if (hashTable[index] == null) hashTable[index] = new StudentNode(students[i], null);
else hashTable[index] = new StudentNode(students[i], hashTable[index]);
}
int result;
do
{
Console.WriteLine("请输入要查询的学生的成绩：");
if (!int.TryParse(Console.ReadLine(), out result)) break;
bool successful = false; //标记查找是否成功
StudentNode node = hashTable[result % 5]; //计算哈希地址
while (node != null)
{
if (node.Student.Result == result) //查找成功
{
Console.WriteLine("学号：{0}\t姓名：{1}\t年级：{2}",
node.Student.Number, node.Student.Name, node.Student.Grade);
successful = true;
}
node = node.Next;
}
if (!successful) Console.WriteLine("无此学生信息！"); //查找失败
} while (result != -1);
Console.ReadLine();
}
static void Main(string[] args)
{
Console.Title = "将学生按成绩进行希尔排序";
StudentList students = new StudentList(20);
Console.WriteLine("排序前的学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}",
students[i].Number, students[i].Name, students[i].Result);
}
for (int increment = 5; increment > 0; increment--)
{
//遍历索引从increment开始的学生信息
for (int i = increment; i < 20; i++)
{
//如果索引为i的学生成绩大于索引为i-increment的学生成绩
//则前i/increment+1个学生成绩已经有序
if (students[i].Result > students[i - increment].Result)
{
Student temp = students[i];
int j = i - increment;
//将索引为i的学生信息插入到其所在分组中合适的位置
for (; j >= 0 && temp.Result > students[j].Result; j -= increment)
{
students[j + increment] = students[j];
}
students[j + increment] = temp;
}
}
}
Console.ReadLine();
Console.Clear();
Console.WriteLine("排序后的学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", students[i].Number, students[i].Name, students[i].Result);
}
Console.ReadLine();
}
//建立大根堆
static void CreateHeap(StudentList students, int n)
{
//从第一个非叶子结点开始遍历
for (int i = (n -1) / 2; i >= 0; i--)
{
int lChild = i * 2 + 1; //左孩子索引
int rChild = i * 2 + 2; //右孩子索引
int max = i; //最大值索引
//将结点i的学生成绩与其左孩子结点的学生成绩比较
if (students[lChild].Result > students[max].Result) max = lChild;
//将结点i的学生成绩与其右孩子结点的学生成绩比较
if (rChild <= n && students[rChild].Result > students[max].Result) max = rChild;
//将成绩最好的结点调整到索引为i的结点上
if (max != i)
{
Student temp = students[i];
students[i] = students[max];
students[max] = temp;
}
}
}
static void Main(string[] args)
{
Console.Title = "查找指定学号的学生信息";
Console.WriteLine("学生学号列表如下：");
StudentList students = new StudentList(20);
for (int i = 0; i < 20; i++)
{
Console.Write(students[i].Number + "\t");
if ((i + 1) % 5 == 0) Console.WriteLine();
}
int number;
do
{
Console.WriteLine("请输入要查询的学生学号：");
if (!int.TryParse(Console.ReadLine(), out number)) number = 0;
int middle = 0; //用于查找的对象索引
int low = 0; //查找区域索引下限
int high = 19; //查找区域索引上限
int flag = -1; //用于标记查找成功时的索引，如果查找失败则为-1
//折半查找学生指定学生信息
while(low <= high)
{
middle = (low + high) / 2;
if (number > students[middle].Number) low = middle + 1;//下一次在右半区域中查找
else if (number < students[middle].Number) high = middle - 1;//下一次在左半区域中查找
else
{
flag = middle;//查找成功，将记录索引存入flag中
break; //跳出查找循环
}
}
if (flag > 0)//查找成功
Console.WriteLine("姓名：{0}\t年级：{1}\t成绩：{2}",
students[flag].Name, students[flag].Grade, students[flag].Result);
else Console.WriteLine("无此学生信息！");//查找失败
} while (number != 0);
Console.ReadLine();
}
static void Main(string[] args)
{
Console.Title = "对学生表的前十位学生按成绩排序";
StudentList students = new StudentList(20);
Console.WriteLine("排序前的学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}",
students[i].Number, students[i].Name, students[i].Result);
}
//遍历索引从1开始的学生信息
for (int i = 1; i < 10; i++)
{
//如果索引为i的学生成绩大于索引为i-1的学生成绩，则前i+1个学生成绩已经有序
if (students[i].Result > students[i - 1].Result)
{
Student temp = students[i];
int j = i - 1;
//将索引为i的学生信息插入到其合适的位置
for (; j >= 0 && temp.Result > students[j].Result; j--)
{
students[j + 1] = students[j];
}
students[j + 1] = temp;
}
}
Console.ReadLine();
Console.Clear();
Console.WriteLine("排序后的学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", students[i].Number, students[i].Name, students[i].Result);
}
Console.ReadLine();
}
static void Main(string[] args)
{
Console.Title = "对学生表的前十位学生按成绩排序";
StudentList students = new StudentList(20);
Console.WriteLine("学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", students[i].Number, students[i].Name, students[i].Result);
}
//正向冒泡排序求最小值
for (int i = 1; i < 20; i++)
{
//成绩差的上浮
if (students[i].Result > students[i - 1].Result)
{
Student temp = students[i];
students[i] = students[i - 1];
students[i - 1] = temp;
}
}
//逆向冒泡排序求最大值
for (int i = 19; i > 0; i--)
{
//成绩好的下沉
if (students[i].Result > students[i - 1].Result)
{
Student temp = students[i];
students[i] = students[i - 1];
students[i - 1] = temp;
}
}
Console.WriteLine("最好成绩为：{0} 最差成绩为：{1}", students[0].Result, students[19].Result);
Console.ReadLine();
}
static void Main(string[] args)
{
Console.Title = "将学生按成绩进行归并排序";
StudentList students = new StudentList(20);
Student[] studentsSort = new Student[20];
Console.WriteLine("排序前的学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", students[i].Number, students[i].Name, students[i].Result);
}
Console.ReadLine();
MergeSort(students, studentsSort, 0, 19);
Console.Clear();
Console.WriteLine("排序后的学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", studentsSort[i].Number, studentsSort[i].Name, studentsSort[i].Result);
}
Console.ReadLine();
}
static void Main(string[] args)
{
Console.Title = "求成绩合格的学生";
StudentList students = new StudentList(20);
Console.WriteLine("排序前学生信息表：");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", students[i].Number, students[i].Name, students[i].Result);
}
Console.ReadLine();
int low = 0, high = 19;
int result = 60; //合格的成绩
Student temp = students[low];
//第一趟快速排序，将学生按成绩分为大于等于60的和小于60的两部分
while (low < high)
{
while (low < high && students[high].Result >= result) high--;
students[low++] = students[high];
while (low < high && students[low].Result <= result) low++;
students[high--] = students[low];
}
students[low] = temp;
if (temp.Result < result) low++;
Console.Clear();
Console.WriteLine("成绩合格的学生信息表：");
for (int i = low; i < 20; i++)
{
Console.WriteLine("学号：{0}\t姓名：{1}\t成绩：{2}", students[i].Number, students[i].Name, students[i].Result);
}
Console.ReadLine();
}
static void Main(string[] args)
{
Console.Title = "将学生信息表顺序倒置";
StudentList students = new StudentList(10); //创建含有10个元素的学生信息表
Console.WriteLine("按顺序输出学生姓名：");
for (int i = 0; i < 10; i++) Console.Write(students[i].Name + "\t");
//将学生表前面的元素与后面的元素互换
for (int i = 0; i < 5; i++)
{
Student temp = students[i];
students[i] = students[9 - i];
students[9 - i] = temp;
}
Console.WriteLine("输出学生信息表倒置后的学生姓名：");
for (int i = 0; i < 10; i++) Console.Write(students[i].Name + "\t");
Console.Read();
}
