Stream 将结果队伍中的字符串姓名作为Student对象的属性，创建Student对象，将集合中的元素都更改为Student类型

下面是一个示例代码：

class Student:
    def __init__(self, name):
        self.name = name

students = []
results = ['Tom', 'Jerry', 'Alice', 'Bob']

students = list(map(lambda name: Student(name), results))

首先定义了一个`Student`类，具有一个`name`属性。然后定义了一个空列表`students`和一个包含字符串姓名的列表`results`。

使用`map`函数将`results`列表中的每个字符串姓名转换为`Student`对象，并将所有结果存储在`students`列表中。

现在`students`列表中包含了四个`Student`对象，可以使用`for`循环遍历列表并访问每个对象的`name`属性。

相关问题

设计一个模板类SET，集合中可以存放不同类型的对象；然后编写一个演示程序利用SET创建并使用整数的集合、字符串的集合以及学生的集合，学生类STUDENT是自己设计的类类型，包括对学生的学号、姓名、年龄、系别等信息的描述及必要的行为。（提示：集合中的元素不允许重复，且元素之间是无序的）SET类的原型可参考如下：template <class T>class SET {private:T elements[MAX_LEN];// 定义元素集合,来记录SET中的元素intN;// 定义元素的实际个数public:SET(); SET(T data[], int n);SET(const SET &obj);~SET();int hasElement(T one); //判断元素one是否在集合中void inputElement(T one); // 向集合中加入一个元素void delElement(T one);// 从集合中删除一个元素void showAllElements(); //显示集合中的所有元素// SET对象之间的运算：交、并、差，分别采用运算符重载实现SET operator+(const SET &obj);SET operator*(const SET &obj);SET operator-(const SET &obj);SET operator=(const SET &obj);};STUDENT类的原型可参考如下：class STUDENT{private:long id;char name[MAX_LEN];char sex;int age;public:STUDENT();STUDENT(const STUDENT& obj);STUDENT(long idd, char namee[], char sexx, int agee);~STUDENT();int operator==(const STUDENT& obj);STUDENT operator=(const STUDENT& obj);// 定义友元函数friend ostream& operator<<(ostream& stream, const STUDENT& obj);};题目说明：1）SET中的数据可以使用固定长度的数组存储，也可以使用动态数组存储，也可

以其他方式存储；

2）在演示程序中，需要创建整数、字符串和学生的集合，并进行交、并、差等运算；

3）在STUDENT类中，需要重载==运算符和=运算符，并定义友元函数ostream& operator<<(ostream& stream, const STUDENT& obj)，用于输出学生信息。

下面是一个可能的实现：

#include <iostream>
#include <cstring>
using namespace std;

const int MAX_LEN = 100;

template <class T>
class SET {
private:
    T elements[MAX_LEN];
    int N;

public:
    SET() {
        N = 0;
    }

    SET(T data[], int n) {
        N = 0;
        for (int i = 0; i < n; i++) {
            inputElement(data[i]);
        }
    }

    SET(const SET &obj) {
        N = obj.N;
        for (int i = 0; i < N; i++) {
            elements[i] = obj.elements[i];
        }
    }

    ~SET() {}

    int hasElement(T one) {
        for (int i = 0; i < N; i++) {
            if (elements[i] == one) {
                return i;
            }
        }
        return -1;
    }

    void inputElement(T one) {
        if (hasElement(one) == -1) {
            elements[N++] = one;
        }
    }

    void delElement(T one) {
        int index = hasElement(one);
        if (index != -1) {
            for (int i = index; i < N - 1; i++) {
                elements[i] = elements[i + 1];
            }
            N--;
        }
    }

    void showAllElements() {
        for (int i = 0; i < N; i++) {
            cout << elements[i] << " ";
        }
        cout << endl;
    }

    SET operator+(const SET &obj) {
        SET result;
        for (int i = 0; i < N; i++) {
            result.inputElement(elements[i]);
        }
        for (int i = 0; i < obj.N; i++) {
            result.inputElement(obj.elements[i]);
        }
        return result;
    }

    SET operator*(const SET &obj) {
        SET result;
        for (int i = 0; i < N; i++) {
            if (obj.hasElement(elements[i]) != -1) {
                result.inputElement(elements[i]);
            }
        }
        return result;
    }

    SET operator-(const SET &obj) {
        SET result;
        for (int i = 0; i < N; i++) {
            if (obj.hasElement(elements[i]) == -1) {
                result.inputElement(elements[i]);
            }
        }
        return result;
    }

    SET operator=(const SET &obj) {
        N = obj.N;
        for (int i = 0; i < N; i++) {
            elements[i] = obj.elements[i];
        }
        return *this;
    }
};

class STUDENT {
private:
    long id;
    char name[MAX_LEN];
    char sex;
    int age;

public:
    STUDENT() {}

    STUDENT(const STUDENT& obj) {
        id = obj.id;
        strcpy(name, obj.name);
        sex = obj.sex;
        age = obj.age;
    }

    STUDENT(long idd, char namee[], char sexx, int agee) {
        id = idd;
        strcpy(name, namee);
        sex = sexx;
        age = agee;
    }

    ~STUDENT() {}

    int operator==(const STUDENT& obj) {
        return (id == obj.id && strcmp(name, obj.name) == 0 && sex == obj.sex && age == obj.age);
    }

    STUDENT operator=(const STUDENT& obj) {
        id = obj.id;
        strcpy(name, obj.name);
        sex = obj.sex;
        age = obj.age;
        return *this;
    }

    friend ostream& operator<<(ostream& stream, const STUDENT& obj) {
        stream << obj.id << " " << obj.name << " " << obj.sex << " " << obj.age;
        return stream;
    }
};

int main() {
    SET<int> intSet1, intSet2;
    intSet1.inputElement(1);
    intSet1.inputElement(2);
    intSet1.inputElement(3);
    intSet2.inputElement(2);
    intSet2.inputElement(3);
    intSet2.inputElement(4);
    SET<int> intSet3 = intSet1 + intSet2;
    SET<int> intSet4 = intSet1 * intSet2;
    SET<int> intSet5 = intSet1 - intSet2;
    cout << "Int Set 1: ";
    intSet1.showAllElements();
    cout << "Int Set 2: ";
    intSet2.showAllElements();
    cout << "Int Set 1 + Int Set 2: ";
    intSet3.showAllElements();
    cout << "Int Set 1 * Int Set 2: ";
    intSet4.showAllElements();
    cout << "Int Set 1 - Int Set 2: ";
    intSet5.showAllElements();

    SET<string> stringSet1, stringSet2;
    stringSet1.inputElement("hello");
    stringSet1.inputElement("world");
    stringSet2.inputElement("world");
    stringSet2.inputElement("!");
    SET<string> stringSet3 = stringSet1 + stringSet2;
    SET<string> stringSet4 = stringSet1 * stringSet2;
    SET<string> stringSet5 = stringSet1 - stringSet2;
    cout << "String Set 1: ";
    stringSet1.showAllElements();
    cout << "String Set 2: ";
    stringSet2.showAllElements();
    cout << "String Set 1 + String Set 2: ";
    stringSet3.showAllElements();
    cout << "String Set 1 * String Set 2: ";
    stringSet4.showAllElements();
    cout << "String Set 1 - String Set 2: ";
    stringSet5.showAllElements();

    STUDENT student1(1, "Alice", 'F', 20), student2(2, "Bob", 'M', 21), student3(3, "Charlie", 'M', 22);
    SET<STUDENT> studentSet1, studentSet2;
    studentSet1.inputElement(student1);
    studentSet1.inputElement(student2);
    studentSet2.inputElement(student2);
    studentSet2.inputElement(student3);
    SET<STUDENT> studentSet3 = studentSet1 + studentSet2;
    SET<STUDENT> studentSet4 = studentSet1 * studentSet2;
    SET<STUDENT> studentSet5 = studentSet1 - studentSet2;
    cout << "Student Set 1: ";
    studentSet1.showAllElements();
    cout << "Student Set 2: ";
    studentSet2.showAllElements();
    cout << "Student Set 1 + Student Set 2: ";
    studentSet3.showAllElements();
    cout << "Student Set 1 * Student Set 2: ";
    studentSet4.showAllElements();
    cout << "Student Set 1 - Student Set 2: ";
    studentSet5.showAllElements();

    return 0;
}

如何从student类的list对象的stream流中获取所有对象并整体转化为字符串

要将整个`Student`对象列表转换为一个字符串，您可以使用流的`map()`方法将每个`Student`对象转换为字符串表示，然后使用`collect()`方法将所有字符串连接起来。以下是一个示例代码：

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

public class Main {
    public static void main(String[] args) {
        List<Student> students = new ArrayList<>();
        students.add(new Student("John", 20));
        students.add(new Student("Alice", 22));
        students.add(new Student("Bob", 19));

        String studentsString = students.stream()
                .map(Student::toString) // 将每个Student对象转为字符串
                .collect(Collectors.joining(", ")); // 将所有字符串连接起来

        System.out.println(studentsString);
    }
}

class Student {
    private String name;
    private int age;

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    @Override
    public String toString() {
        return "Name: " + name + ", Age: " + age;
    }
}

在这个示例中，我们首先创建了一个包含三个`Student`对象的`List`。然后，我们使用流的`map()`方法将每个`Student`对象转换为字符串表示，这里使用了对象的`toString()`方法。最后，我们使用`collect()`方法和`Collectors.joining()`将所有字符串连接起来，使用逗号和空格作为分隔符。最终，将整个字符串打印出来。

请注意，这里的`toString()`方法是根据`Student`类的实现来进行的，您可以根据实际情况修改`Student`类和转换逻辑。