1 #ifndef VECTOR_HPP
  2 #define VECTOR_HPP
  3 
  4 #include <iostream>
  5 #include <stdexcept> // 用于异常处理
  6 
  7 using namespace std;
  8 
  9 template <typename T>
 10 class Vector {  // 类名修改为 MyVector，避免与 std::vector 冲突
 11 private:
 12     T* data;        // 动态数组的指针
 13     size_t size;    // 数组的大小
 14 
 15 public:
 16     // 构造函数
 17     Vector(size_t n, const T& value = T()) {
 18         if (n < 0) {
 19             throw length_error("Vector construction: negative size");
 20         }
 21         size = n;
 22         data = new T[size];
 23         for (size_t i = 0; i < size; ++i) {
 24             data[i] = value;
 25         }
 26     }
 27 
 28     // 拷贝构造函数
 29     Vector(const Vector& other) {
 30         size = other.size;
 31         data = new T[size];
 32         for (size_t i = 0; i < size; ++i) {
 33             data[i] = other.data[i];
 34         }
 35     }
 36 
 37     // 析构函数
 38     ~Vector() {
 39         delete[] data;
 40     }
 41 
 42     // 返回大小
 43     size_t get_size() const {
 44         return size;
 45     }
 46 
 47     // 带边界检查的 at()
 48     T& at(size_t index) {
 49         if (index >= size) {
 50             throw out_of_range("Vector: index out of range");
 51         }
 52         return data[index];
 53     }
 54 
 55     const T& at(size_t index) const {
 56         if (index >= size) {
 57             throw out_of_range("Vector: index out of range");
 58         }
 59         return data[index];
 60     }
 61 
 62     // 重载输出流操作符
 63     friend ostream& operator<<(ostream& os, const Vector<T>& v) {
 64         for (size_t i = 0; i < v.size; ++i) {
 65             os << v.data[i] << " ";
 66         }
 67         return os;
 68     }
 69 };
 70 
 71 // 输出函数：简化输出向量内容
 72 template <typename T>
 73 void output(const Vector<T>& v) {
 74     cout << v << endl;
 75 }
 76 
 77 #endif
 78 
 79 
 80 
 81 
 82 #include <iostream>
 83 #include "Vector.hpp"
 84 
 85 void test1() {
 86     using namespace std;
 87 
 88     int n;
 89     cout << "Enter n: ";
 90     cin >> n;
 91     
 92     Vector<double> x1(n);
 93     for(auto i = 0; i < n; ++i)
 94         x1.at(i) = i * 0.7;
 95 
 96     cout << "x1: "; output(x1);
 97 
 98     Vector<int> x2(n, 42);
 99     const Vector<int> x3(x2);
100 
101     cout << "x2: "; output(x2);
102     cout << "x3: "; output(x3);
103 
104     x2.at(0) = 77;
105     x2.at(1) = 777;
106     cout << "x2: "; output(x2);
107     cout << "x3: "; output(x3);
108 }
109 
110 void test2() {
111     using namespace std;
112 
113     int n, index;
114     while(cout << "Enter n and index: ", cin >> n >> index) {
115         try {
116             Vector<int> v(n, n);
117             v.at(index) = -999;
118             cout << "v: "; output(v);
119         }
120         catch (const exception &e) {
121             cout << e.what() << endl;
122         }
123     }
124 }
125 
126 int main() {
127     cout << "测试1: 模板类接口测试\n";
128     test1();
129 
130     cout << "\n测试2: 模板类异常处理测试\n";
131     test2();
132 }
task4

 1 #include <iostream>
 2 #include <fstream>
 3 #include <vector>
 4 #include <algorithm>
 5 #include <sstream>
 6 
 7 using namespace std;
 8 
 9 // 定义结构体表示学生信息
10 struct Student {
11     string id;       // 学号
12     string name;     // 姓名
13     string major;    // 专业
14     int score;       // 分数
15 };
16 
17 // 自定义排序规则
18 bool compareStudents(const Student& a, const Student& b) {
19     if (a.major != b.major) {
20         // 专业按字典序排序
21         return a.major < b.major;
22     } else {
23         // 在相同专业内按分数降序排序
24         return a.score > b.score;
25     }
26 }
27 
28 int main() {
29     ifstream inputFile("data5.txt");  // 输入文件
30     ofstream outputFile("ans5.txt");  // 输出文件
31 
32     if (!inputFile.is_open()) {
33         cerr << "Error: Unable to open input file!" << endl;
34         return 1;
35     }
36 
37     vector<Student> students;
38     string line;
39 
40     // 读取文件的每一行数据
41     while (getline(inputFile, line)) {
42         stringstream ss(line);
43         Student student;
44         ss >> student.id >> student.name >> student.major >> student.score;
45         students.push_back(student);
46     }
47 
48     inputFile.close();  // 关闭输入文件
49 
50     // 对学生信息排序
51     sort(students.begin(), students.end(), compareStudents);
52 
53     // 输出到屏幕和文件
54     cout << "Sorted Student Information:" << endl;
55     for (const auto& student : students) {
56         cout << student.id << " " << student.name << " " << student.major << " " << student.score << endl;
57         outputFile << student.id << " " << student.name << " " << student.major << " " << student.score << endl;
58     }
59 
60     outputFile.close();  // 关闭输出文件
61 
62     return 0;
63 }
task5