任务1：
task1.cpp
1 Complex.hpp:
2 #pragma once
3
4 #include <iostream>
5 #include <stdexcept>
6
7 // 声明
8 ////////////////////////////////////////////////////
9 // 复数模板类声明
10 template<typename T>
11 class Complex {
12 public:
13 Complex(T r = 0, T i = 0);
14 Complex(const Complex<T> &c);
15
16 T get_real() const;
17 T get_imag() const;
18
19 // 重载+=为成员函数
20 Complex<T>& operator+=(const Complex<T> &c);
21
22 // 重载<<、>>为友元函数
23 template<typename T1>
24 friend std::ostream& operator<<(std::ostream &out, const Complex<T1> &c);
25
26 template<typename T1>
27 friend std::istream& operator>>(std::istream &in, Complex<T1> &c);
28
29 private:
30 T real, imag;
31 };
32
33 // 普通函数声明
34 // 重载+用于Complex类型
35 template<typename T>
36 Complex<T> operator+(const Complex<T> &c1, const Complex<T> &c2);
37
38 // 重载==用于Complex类型
39 template<typename T>
40 bool operator==(const Complex<T> &c1, const Complex<T> &c2);
41
42
43 // 实现
44 ////////////////////////////////////////////////////
45 // 成员函数模板实现
46 template<typename T>
47 Complex<T>::Complex(T r, T i): real{r}, imag{i} {
48 }
49
50 template<typename T>
51 Complex<T>::Complex(const Complex<T> &c): real{c.real}, imag{c.imag} {
52 }
53
54 template<typename T>
55 T Complex<T>::get_real() const {
56 return real;
57 }
58
59 template<typename T>
60 T Complex<T>::get_imag() const {
61 return imag;
62 }
63
64 // 重载+=为成员函数
65 template<typename T>
66 Complex<T>& Complex<T>::operator+=(const Complex<T> &c) {
67 real += c.real;
68 imag += c.imag;
69
70 return *this;
71 }
72
73 ///////////////////////////////////////
74 // 友元函数模板实现
75 template<typename T1>
76 std::ostream& operator<<(std::ostream &out, const Complex<T1> &c) {
77 if(c.imag >= 0)
78 out << c.real << " + " << c.imag << "i";
79 else
80 out << c.real << " - " << -c.imag << "i";
81
82 return out;
83 }
84
85 template<typename T1>
86 std::istream& operator>>(std::istream &in, Complex<T1> &c) {
87 in >> c.real >> c.imag;
88
89 return in;
90 }
91
92 ///////////////////////////////////////
93 // 普通函数模板实现
94 // 重载+用于Complex类型
95 template<typename T>
96 Complex<T> operator+(const Complex<T> &c1, const Complex<T> &c2) {
97 return Complex<T>(c1.get_real()+c2.get_real(),
98 c1.get_imag()+c2.get_imag());
99 }
100
101 // 重载==用于Complex类型
102 template<typename T>
103 bool operator==(const Complex<T> &c1, const Complex<T> &c2) {
104 return c1.get_real() == c2.get_real() &&
105 c1.get_imag() && c2.get_imag();
106 }
107
108 task1.cpp:
109 #include "Complex.hpp"
110 #include <iostream>
111 #include <fstream>
112 #include <stdexcept>
113
114 void test1();
115 void test2();
116
117 int main() {
118 using namespace std;
119
120 cout << "测试1: 复数模板类测试" << endl;
121 test1();
122
123 cout << "\n测试2: 文件I/O测试" << endl;
124 test2();
125 }
126
127 void test1() {
128 using namespace std;
129
130 Complex<double> c1{3.5, 2}, c2;
131 cout << "Enter c2: ";
132 cin >> c2;
133 cout << "c1 = " << c1 << endl;
134 cout << "c2 = " << c2 << endl;
135 cout << "c1 == c2: " << boolalpha << (c1 == c2) << endl;
136
137 cout << "c1 + c2 = " << c1 + c2 << endl;
138 c1 += c2;
139 cout << "c1.real = " << c1.get_real() << endl;
140 cout << "c1.imag = " << c1.get_imag() << endl;
141
142 cout << "c1 == c2: " << boolalpha << (c1 == c2) << endl;
143 }
144
145 void test2() {
146 using namespace std;
147
148 Complex<int> c1{1, 2}, c2{9, -7};
149 ofstream out("ans.txt");
150 if(!out.is_open()) {
151 cout << "fail to open file ans.txt to write\n";
152 return;
153 }
154
155 out << "c1 = " << c1 << endl;
156 out << "c2 = " << c2 << endl;
157 out << "c1 + c2 = " << c1 + c2 << endl;
158 out << "(c1 == c2) = " << boolalpha << (c1 == c2) << endl;
159
160 out.close();
161 cout << "测试ok!" << endl;
162 }
View Code
任务2：
task2.cpp
1 Contestant.hpp:
2 #pragma once
3
4 #include <iostream>
5 #include <iomanip>
6 #include <string>
7
8 using std::string;
9 using std::ostream;
10 using std::istream;
11 using std::setw;
12 using std::setprecision;
13 using std::setiosflags;
14 using std::ios_base;
15
16 // Contestant类声明
17 class Contestant {
18 public:
19 Contestant() = default;
20 ~Contestant() = default;
21
22 int get_num() const { return num; }
23 float get_time_usage() const { return time_usage; }
24
25 friend ostream& operator<<(ostream &out, const Contestant &c);
26 friend istream& operator>>(istream &in, Contestant &c);
27
28 private:
29 string no; // 学号
30 string name; // 姓名
31 string major; // 专业
32 int num; // 解题数
33 float time_usage; // 总用时
34 };
35
36 // 友元函数实现
37 // 重载流插入运算符<<
38 ostream& operator<<(ostream &out, const Contestant &c) {
39 out << setiosflags(ios_base::left);
40 out << setw(15) << c.no
41 << setw(15) << c.name
42 << setw(15) << c.major
43 << setw(5) << c.num
44 << setprecision(2) << c.time_usage;
45
46 return out;
47 }
48
49 // 重载流提取运算符>>
50 istream& operator>>(istream &in, Contestant &c) {
51 in >> c.no >> c.name >> c.major >> c.num >> c.time_usage;
52
53 return in;
54 }
55
56 utils.hpp:
57 #include "Contestant.hpp"
58 #include <fstream>
59 #include <iostream>
60 #include <string>
61 #include <vector>
62
63 // 排序函数
64 // 按解题数比较，解题数相同的情况下，按总用时比较，总用时越少，排名越靠前
65 bool compare_by_solutionInfo(const Contestant &c1, const Contestant &c2) {
66 if(c1.get_num() > c2.get_num())
67 return true;
68
69 if(c1.get_num() == c2.get_num())
70 return c1.get_time_usage() < c2.get_time_usage();
71
72 return false;
73 }
74
75 // 把vector<Constestant>对象中的元素插入到输出流out
76 void output(std::ostream &out, const std::vector<Contestant> &v) {
77 for(auto &i: v)
78 out << i << std::endl;
79 }
80
81
82 // 把vector<Contestant>对象中的元素写到filename文件中
83 void save(const std::string &filename, std::vector<Contestant> &v) {
84 using std::ofstream;
85
86 ofstream out(filename);
87 if(!out.is_open()) {
88 std::cout << "fail to open file to write\n";
89 return;
90 }
91
92 output(out, v);
93 out.close();
94 }
95
96 // 从文件filename读取参赛选手信息到vector<Contestant>对象
97 void load(const std::string &filename, std::vector<Contestant> &v) {
98 using std::ifstream;
99
100 ifstream in(filename);
101 if(!in.is_open()) {
102 std::cout << "fail to open file to read\n";
103 return;
104 }
105
106 std::string title_line;
107 getline(in, title_line); // 跳过标题行
108
109 int first_column;
110 Contestant t;
111 while(in >> first_column >> t)
112 v.push_back(t);
113
114 in.close();
115 }
116
117
118 task2.cpp:
119 #include "Contestant.hpp"
120 #include "utils.hpp"
121 #include <iostream>
122 #include <vector>
123 #include <algorithm>
124
125
126 void test() {
127 using namespace std;
128
129 vector<Contestant> v;
130
131 load("data2.txt", v); // 从文件加载选手信息到对象v
132 sort(v.begin(), v.end(), compare_by_solutionInfo); // 按解题情况排序
133 output(cout, v); // 输出对象v中信息到屏幕
134 save("ans.txt", v); // 把对象v中选手信息保存到文件
135 }
136
137 int main() {
138 test();
139 }
View Code
任务3：
task3.cpp
1 Triangle.hpp:
2 #include <iostream>
3 #include <stdexcept>
4 #include <cmath>
5
6 using namespace std;
7
8 class Triangle {
9 public:
10 Triangle(double s1, double s2, double s3);
11 ~Triangle() = default;
12
13 double area() const;
14
15 private:
16 double a, b, c;
17 };
18
19 Triangle::Triangle(double s1, double s2, double s3): a{s1}, b{s2}, c{s3} {
20 if(a <= 0 || b <= 0 || c <= 0)
21 throw invalid_argument("边长出现负值");
22
23 if(a+b <= c || b+c <= a || a+c <= b)
24 throw invalid_argument("不满足任意两边之和大于第三边");
25 }
26
27 double Triangle::area() const {
28 double s = (a + b + c)/2;
29 return sqrt(s*(s-a)*(s-b)*(s-c));
30 }
31
32 task3.cpp:
33 #include "Triangle.hpp"
34 #include <iostream>
35 #include <fstream>
36
37 void test() {
38 using namespace std;
39
40 cout << "从文件读入三角形三边边长，计算面积" << endl;
41
42 ifstream in("data3.txt");
43 if(!in.is_open()) {
44 cout << "fail to open file to read\n";
45 return;
46 }
47
48 double a,b,c;
49 do {
50 cout << "三角形边长: ";
51 in >> a >> b >> c;
52 cout << a << " " << b << " " << c << endl;
53
54 try {
55 Triangle t(a, b, c);
56 cout << "三角形面积: " << t.area() << endl << endl;
57 }catch(const exception &e) {
58 cout << "error: " << e.what() << endl << endl;
59 }
60
61 if(in.peek() == EOF)
62 break;
63 } while(1);
64
65 in.close();
66 }
67
68 int main() {
69 test();
70 }
View Code
任务4：
task4.cpp
1 Vector.hpp:
2 #include<iostream>
3
4 using namespace std;
5
6 template<typename T>
7 class Vector {
8 private:
9 T* ptr;
10 int size;
11 public:
12 Vector(int n) {
13 if (n < 0) {
14 throw length_error("Vector constructor: negative size");
15 }
16 else {
17 ptr = new T[n];
18 size = n;
19 }
20 }
21 Vector(int n, T data) {
22 if (n < 0) {
23 throw length_error("Vector constructor: negative size");
24 }
25 else {
26 ptr = new T[n];
27 size = n;
28 for (int i = 0; i < size; i++) {
29 ptr[i] = data;
30 }
31 }
32 }
33 Vector(Vector<T>& v) {
34 size = v.get_size();
35 ptr = new T[size];
36 for (int i = 0; i < size; i++) {
37 ptr[i] = v.at(i);
38 }
39 }
40 int get_size() {
41 return size;
42 }
43 T& at(int index) const {
44 if (index > size - 1) {
45 throw overflow_error("Vector: index out of range");
46 }
47 return ptr[index];
48 }
49 T& operator[](int index) {
50 if (index > size - 1) {
51 throw overflow_error("Vector: index out of range");
52 }
53 return ptr[index];
54 }
55 template<typename T>
56 friend void output(const Vector<T>& v);
57 };
58
59 template<typename T>
60 void output(const Vector<T>& v) {
61 for (int i = 0; i < v.size; i++) {
62 cout << v.at(i) << ' ';
63 }
64 cout << endl;
65 }
66
67 task4.cpp:
68 #include <iostream>
69 #include "Vector.hpp"
70
71 void test1() {
72 using namespace std;
73
74 int n;
75 cout << "Enter n: ";
76 cin >> n;
77
78 Vector<double> x1(n);
79 for (auto i = 0; i < n; ++i)
80 x1.at(i) = i * 0.7;
81
82 cout << "x1: "; output(x1);
83
84 Vector<int> x2(n, 42);
85 const Vector<int> x3(x2);
86
87 cout << "x2: "; output(x2);
88 cout << "x3: "; output(x3);
89
90 x2.at(0) = 77;
91 x2.at(1) = 777;
92 cout << "x2: "; output(x2);
93 cout << "x3: "; output(x3);
94 }
95
96 void test2() {
97 using namespace std;
98
99 int n, index;
100 while (cout << "Enter n and index: ", cin >> n >> index) {
101 try {
102 Vector<int> v(n, n);
103 v.at(index) = -999;
104 cout << "v: "; output(v);
105 }
106 catch (const exception& e) {
107 cout << e.what() << endl;
108 }
109 }
110 }
111
112 int main() {
113 cout << "测试1: 模板类接口测试\n";
114 test1();
115
116 cout << "\n测试2: 模板类异常处理测试\n";
117 test2();
118 }
View Code
任务5：
task5.cpp
1 Student.hpp:
2 #pragma once
3 #include<iostream>
4 using namespace std;
5 class Student {
6 public:
7 Student(string id, string name, string major, int score) {
8 this->id = id; this->name = name; this->major = major; this->score = score;
9 }
10 string getId() {
11 return id;
12 }
13 string getName() {
14 return name;
15 }
16 string getMajor() {
17 return major;
18 }
19 int getScore() {
20 return score;
21 }
22 friend bool Compare(Student& s1, Student& s2);
23 private:
24 string id;
25 string name;
26 string major;
27 int score;
28 };
29 bool Compare(Student& s1, Student& s2) {
30 if (s1.major.compare(s2.major) > 0) {
31 return false;
32 }
33 else if (s1.major.compare(s2.major) == 0) {
34 if (s1.score < s2.score) {
35 return false;
36 }
37 }
38 return true;
39 }
40
41 task5.cpp:
42 #include<iostream>
43 #include"student.hpp"
44 #include<fstream>
45 #include<vector>
46 #include<algorithm>
47 using namespace std;
48 int main() {
49 ifstream fin;
50 fin.open("data5.txt");
51 string lst;
52 for (int i = 0; i < 4; i++) {
53 fin >> lst;
54 }
55 vector<Student> stulist;
56 string id, name, major;
57 int score;
58 while (fin >> id >> name >> major >> score) {
59 stulist.push_back(Student(id, name, major, score));
60 }
61 fin.close();
62 sort(stulist.begin(), stulist.end(), Compare);
63 ofstream fopen;
64 fopen.open("ans.txt");
65 for (auto& stu : stulist) {
66 cout << stu.getId() << " " << stu.getName() << " " << stu.getMajor() << " " << stu.getScore() << endl;
67 }
68 }
View Code
标签：std,文件,const,get,Complex,实验,return,include,模板 From： https://www.cnblogs.com/Altairsss/p/18618930