实验六
实验任务四
代码
vector.hpp
1 #ifndef VECTOR_HPP 2 #define VECTOR_HPP 3 4 #include <stdexcept> 5 #include <iostream> // 确保可以使用std::cout和std::endl 6 7 template <typename T> 8 class Vector { 9 private: 10 T* data_; 11 int size_; 12 public: 13 // 默认构造函数 14 Vector(): data_(nullptr), size_(0) {} 15 16 // 构造函数：指定大小 17 Vector(int n) : data_(nullptr), size_(0) { 18 if (n < 0) { 19 throw std::length_error("negative size"); 20 } 21 if (n > 0) { 22 data_ = new T[n](); // 默认初始化 23 size_ = n; 24 } 25 } 26 27 // 构造函数：指定大小和初始值 28 Vector(int n, const T &value) : data_(nullptr), size_(0) { 29 if (n < 0) { 30 throw std::length_error("negative size"); 31 } 32 if (n > 0) { 33 data_ = new T[n]; 34 size_ = n; 35 for (int i = 0; i < n; ++i) { 36 data_[i] = value; 37 } 38 } 39 } 40 41 // 拷贝构造函数：深拷贝 42 Vector(const Vector<T> &other) : data_(nullptr), size_(0) { 43 if (other.size_ > 0) { 44 data_ = new T[other.size_]; 45 size_ = other.size_; 46 for (int i = 0; i < size_; ++i) { 47 data_[i] = other.data_[i]; 48 } 49 } 50 } 51 52 // 析构函数 53 ~Vector() { 54 delete[] data_; 55 } 56 57 // 返回大小 58 int get_size() const { 59 return size_; 60 } 61 62 // at()函数，带范围检查 63 T& at(int i) { 64 if (i < 0 || i >= size_) { 65 throw std::out_of_range("Vector: index out of range"); 66 } 67 return data_[i]; 68 } 69 70 const T& at(int i) const { 71 if (i < 0 || i >= size_) { 72 throw std::out_of_range("Vector: index out of range"); 73 } 74 return data_[i]; 75 } 76 77 // 重载[]，同样进行范围检查 78 T& operator[](int i) { 79 if (i < 0 || i >= size_) { 80 throw std::out_of_range("Vector: index out of range"); 81 } 82 return data_[i]; 83 } 84 85 const T& operator[](int i) const { 86 if (i < 0 || i >= size_) { 87 throw std::out_of_range("Vector: index out of range"); 88 } 89 return data_[i]; 90 } 91 92 // 友元函数：输出Vector内容 93 friend void output(const Vector<T> &v) { 94 for (int i = 0; i < v.size_; ++i) { 95 std::cout << v.data_[i]; 96 if (i < v.size_ - 1) std::cout << ", "; 97 } 98 std::cout << std::endl; 99 } 100 }; 101 102 #endif
task4.cpp
1 #include <iostream> 2 #include "Vector.hpp" 3 using namespace std; 4 void test1() { 5 using namespace std; 6 7 int n; 8 cout << "Enter n: "; 9 cin >> n; 10 11 Vector<double> x1(n); 12 for(auto i = 0; i < n; ++i) 13 x1.at(i) = i * 0.7; 14 15 cout << "x1: "; output(x1); 16 17 Vector<int> x2(n, 42); 18 const Vector<int> x3(x2); 19 20 cout << "x2: "; output(x2); 21 cout << "x3: "; output(x3); 22 23 x2.at(0) = 77; 24 x2.at(1) = 777; 25 cout << "x2: "; output(x2); 26 cout << "x3: "; output(x3); 27 } 28 29 void test2() { 30 using namespace std; 31 32 int n, index; 33 while(cout << "Enter n and index: ", cin >> n >> index) { 34 try { 35 Vector<int> v(n, n); 36 v.at(index) = -999; 37 cout << "v: "; output(v); 38 } 39 catch (const exception &e) { 40 cout << e.what() << endl; 41 } 42 } 43 } 44 45 int main() { 46 cout << "测试1: 模板类接口测试\n"; 47 test1(); 48 49 cout << "\n测试2: 模板类异常处理测试\n"; 50 test2(); 51 }
编译结果
实验任务五
代码
task5.cpp
1 #include <iostream> 2 #include <fstream> 3 #include <string> 4 #include <vector> 5 #include <algorithm> 6 using namespace std; 7 8 struct Student { 9 int id; 10 string name; 11 string major; 12 int score; 13 }; 14 15 int main() { 16 ifstream fin("data5.txt"); 17 if (!fin) { 18 cout << "无法打开data5.txt文件" << endl; 19 return 1; 20 } 21 22 { 23 string header; 24 getline(fin, header); 25 } 26 27 vector<Student> students; 28 Student temp; 29 30 while (fin >> temp.id >> temp.name >> temp.major >> temp.score) { 31 students.push_back(temp); 32 } 33 fin.close(); 34 35 36 sort(students.begin(), students.end(), [](const Student &a, const Student &b) { 37 if (a.major == b.major) { 38 return a.score > b.score; 39 } 40 return a.major < b.major; 41 }); 42 43 44 for (auto &s : students) { 45 cout << s.id << "\t" << s.name << "\t" << s.major << "\t" << s.score << endl; 46 } 47 48 ofstream fout("ans5.txt"); 49 for (auto &s : students) { 50 fout << s.id << "\t" << s.name << "\t" << s.major << "\t" << s.score << "\n"; 51 } 52 fout.close(); 53 54 return 0; 55 }
编译结果
