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1 项目内容及要求

本项目通过设计一个抽象向量类模板，以及一个通用的向量类模板和一个字符串类作为其派生类，以满足各种应用场景中的数据存储和处理需求。

项目内容：

1. 抽象向量类模板。
2. 派生向量类。
3. 派生字符串类。
4. 测试及异常处理。
5. 联合测试

2.1 抽象向量类模板

2.1.1 数据成员设计

int  num;//向量的维度
T* p;//存储元素的数组 

2.1.2 成员函数设计

VECTOR(int size = 0, const T* x = NULL)//构造函数
VECTOR(const VECTOR& v)//拷贝构造函数
virtual ~VECTOR()//虚析构函数
VECTOR& operator=(const VECTOR& v)//赋值运算符重载
T& operator[](int index)//用于访问特定位置的元素
void resize(int size)//重设容器大小
virtual void Output(ostream& out) const = 0;//纯虚函数
virtual void Input(istream& in) = 0;//纯虚函数

2.2 派生向量类模板

2.2.1 定义纯虚函数

void Output(ostream& out) const
{if (__super::num == 0) out << "( )";else{out << "(" << __super::p[0];for (int i = 1; i < __super::num; i++){out << "," << __super::p[i];}out << ")" << endl;}
}void Input(istream& in)
{char c;T x;__super::resize(0);in >> c;if (c != '(') return;while (in >> x){__super::resize(__super::num + 1);__super::p[__super::num - 1] = x;in >> c;if (c == ')') break;}
}

2.2.2 成员函数设计

Vector(int size = 0, const T* x = NULL)//构造函数 
Vector operator+(const Vector& v)//+运算符重载 

2.2.3 测试及异常处理

int TestVector()
{int a[10] = { 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 };double x[8];for (int i = 0; i < 8; i++)x[i] = sqrt(double(i));Vector<int> vi1(10, a), vi2(5, a + 5);Vector<double> vd1(8, x), vd2(3, x);cout << "原始数据：" << endl;cout << "vi1 = " << vi1 << "\nvi2 = " << vi2<< "\nvd1 = " << vd1 << "\nvd2 = " << vd2 << endl;cout << "调整维数到5：" << endl;vi1.resize(5);vi2.resize(5);vd1.resize(5);vd2.resize(5);cout << "vi1 = " << vi1 << "\nvi2 = " << vi2<< "\nvd1 = " << vd1 << "\nvd2 = " << vd2 << endl;cout << "\n将数据写入文件 vector.txt 中..." << endl;ofstream outfile("vector.txt");outfile << vi1 << '\n'<< vi2						<< vd1 << '\n' << vd2 << endl;outfile.close();cout << "\n清除对象的数据(即调整维数到0)..." << endl;vi1.resize(0);vi2.resize(0);vd1.resize(0);vd2.resize(0);cout << "vi1 = " << vi1 << "\nvi2 = " << vi2<< "\nvd1 = " << vd1 << "\nvd2 = " << vd2 << endl;cout << "\n从文件 vector.txt 中读取的数据：" << endl;ifstream infile("vector.txt");infile >> vi1 >> vi2 >> vd1 >> vd2;infile.close();cout << "vi1 = " << vi1 << "\nvi2 = " << vi2<< "\nvd1 = " << vd1 << "\nvd2 = " << vd2 << endl;cout << "\nvi1 + vi2 = " << vi1 + vi2<< "\nvd1 + vd2 = " << vd1 + vd2 << endl;cout << "\n异常处理测试" << endl;Vector<int> v;cout << "请输入一个整数向量。如 (1, 3, 5, 7)" << endl;try{cin >> v;//如果格式错误，则抛出异常}catch (const char* str){cout << str << endl;return 0;}return 0;
}

运行结果：

2.3 派生字符串类

2.3.1 定义纯虚函数

void Output(ostream& out) const
{for (int i = 0; i < __super::num; i++){out << p[i];}
}void Input(istream& in)
{string temp;in >> temp;*this = temp.c_str();
}

2.3.2 成员函数设计

String(const char* x = "")//构造函数  
String operator+(const String& s)//+运算符重载 

2.3.3 测试及异常处理

int TestString()
{String str1 = "Hello", str2 = str1, str3;// 转换构造		拷贝构造 	默认构造cout << "原始数据（双引号是另外添加的）：" << endl;cout << "str1 = \"" << str1<< "\"\nstr2 = \"" << str2<< "\"\nstr3 = \"" << str3 << "\"" << endl;str3 = str2;				// 赋值运算str1 = "C++ program.";str2 = str3 + ", world!";	// 拼接运算cout << "str1 = \"" << str1<< "\"\nstr2 = \"" << str2<< "\"\nstr3 = \"" << str3 << "\"" << endl;cout << "\n将数据写入文件 string.txt 中..." << endl;ofstream outfile("string.txt");outfile << str1 << '\n'<< str2 << '\n'<< str3 << endl;outfile.close();cout << "\n清除对象的数据（即调整长度到0）..." << endl;str1.resize(0);str2.resize(0);str3.resize(0);cout << "str1 = \"" << str1<< "\"\nstr2 = \"" << str2<< "\"\nstr3 = \"" << str3 << "\"" << endl;cout << "\n从文件 string.txt 中读取的数据：" << endl;ifstream infile("string.txt");infile >> str1>> str2>> str3;infile.close();cout << "str1 = \"" << str1<< "\"\nstr2 = \"" << str2<< "\"\nstr3 = \"" << str3 << "\"" << endl;cout << "\n异常处理测试" << endl;String str4 = "Hello";try{cout << str4 << endl;cout << str4[10] << endl;//越界访问，抛出异常}catch (const char* str){cout << str << endl;return 0;}return 0;
}

运行结果：

3 联合测试

#include "Vec.h"int TestVector(), TestString(), Test();void menu()
{cout << "\n1 --- testing Vector          [v]"<< "\n2 --- testing String          [s]"<< "\n3 --- testing Vector & String [m]"<< "\n0 --- exit                    [q]"<< endl;
}int main()
{char choice = '0';do{menu();cin >> choice;switch (choice){case '1':case 'v':case 'V':	TestVector();	break;case '2':case 's':case 'S':	TestString();	break;case '3':case 'm':case 'M':	Test();			break;case '0':case 'q':case 'Q':case 27:	choice = 0;		break;default:	cout << "选择错误，重新选择" << endl;	break;}} while (choice);return 0;
}int Test()
{Vector<int> v;String str;cout << "请输入一个整数向量。如 (1, 3, 5, 7)" << endl;try{cin >> v;}catch (const char* str) { cout << str << endl;return 0;}cout << v << endl;cin.sync();			// 刷新输入流缓冲区（目的是读取并丢弃向量后的换行符）cout << "请输入一个字符串。如 abc 12345   xyz" << endl;cin >> str;cout << str << endl;cout << "\n将数据写入文件 output.txt 中..." << endl;ofstream outfile("output.txt");outfile << v << endl<< str << endl;outfile.close();cout << "\n清除对象的数据..." << endl;v.resize(0);str.resize(0);cout << "向量：" << v << endl<< "字符串：\"" << str << "\"" << endl;cout << "\n从文件 output.txt 中读取的数据：" << endl;ifstream infile("output.txt");infile >> v;infile >> str;infile.close();cout << "向量：" << v << endl<< "字符串：\"" << str << "\"" << endl;return 0;
}

运行结果：

4 完整代码

4.1 Vec.h

#pragma once
#define _CRT_SECURE_NO_WARNINGS	1
#include <iostream>
#include <fstream>
#include <string>
using namespace std;template <typename T> class VECTOR
{
public:VECTOR(int size = 0, const T* x = NULL){num = (size > 0) ? size : 0;p = NULL;if (num > 0){p = new T[num];for (int i = 0; i < num; i++)p[i] = (x == NULL) ? 0 : x[i];}}VECTOR(const VECTOR& v){num = v.num;p = NULL;if (num > 0){p = new T[num];for (int i = 0; i < num; i++)p[i] = v.p[i];}}virtual ~VECTOR(){if (p != NULL) delete[] p;}VECTOR& operator=(const VECTOR& v){if (num != v.num){if (p != NULL) delete[] p;p = new T[num = v.num];}for (int i = 0; i < num; i++)p[i] = v.p[i];return *this;}T& operator[](int index){if (index >= num) throw "越界访问";else return p[index];}void resize(int size){if (size < 0 || size == num) return;else if (size == 0){if (p != NULL) delete[] p;num = 0;p = NULL;}else{T* temp = p;p = new T[size];for (int i = 0; i < size; i++)p[i] = (i < num) ? temp[i] : 0;num = size;delete[] temp;}}virtual void Output(ostream& out) const = 0;virtual void Input(istream& in) = 0;int num;//向量的维度T* p;//存储元素的数组
};template <typename T> ostream& operator<<(ostream& out, const VECTOR<T>& v)
{v.Output(out);return out;
}template <typename T> istream& operator>>(istream& in, VECTOR<T>& v)
{v.Input(in);return in;
}template <typename T> class Vector :public VECTOR<T>
{
public:Vector(int size = 0, const T* x = NULL) :VECTOR<T>(size, x) {}void Output(ostream& out) const{if (__super::num == 0) out << "( )";else{out << "(" << __super::p[0];for (int i = 1; i < __super::num; i++){out << "," << __super::p[i];}out << ")" << endl;}}void Input(istream& in){char c;T x;__super::resize(0);in >> c;if (c != '(')	throw "格式错误";while (in >> x){__super::resize(__super::num + 1);__super::p[__super::num - 1] = x;in >> c;if (c == ')') break;}}Vector operator+(const Vector& v){Vector Add;if (__super::num == v.__super::num){Add.resize(__super::num);for (int i = 0; i < __super::num; i++){Add[i] = __super::p[i] + v.__super::p[i];}}return Add;}};class String : public VECTOR<char>
{
public:String(const char* x = "") : VECTOR<char>(strlen(x), x) { }void Output(ostream& out) const{for (int i = 0; i < __super::num; i++){out << p[i];}}void Input(istream& in){string temp;in >> temp;*this = temp.c_str();}String operator+(const String& s){int i, j;String add;add.__super::num = __super::num + s.__super::num;add.p = new char[add.__super::num];for (i = 0; i < __super::num; i++){add.p[i] = p[i];}for (j = 0; j < s.__super::num; j++){add.p[i + j] = s.p[j];}return add;}};

4.2 Test.cpp

#include "Vec.h"int TestVector(), TestString(), Test();void menu()
{cout << "\n1 --- testing Vector          [v]"<< "\n2 --- testing String          [s]"<< "\n3 --- testing Vector & String [m]"<< "\n0 --- exit                    [q]"<< endl;
}int main()
{char choice = '0';do{menu();cin >> choice;switch (choice){case '1':case 'v':case 'V':	TestVector();	break;case '2':case 's':case 'S':	TestString();	break;case '3':case 'm':case 'M':	Test();			break;case '0':case 'q':case 'Q':case 27:	choice = 0;		break;default:	cout << "选择错误，重新选择" << endl;	break;}} while (choice);return 0;
}int Test()
{Vector<int> v;String str;cout << "请输入一个整数向量。如 (1, 3, 5, 7)" << endl;try{cin >> v;}catch (const char* str) { cout << str << endl;return 0;}cout << v << endl;cin.sync();			// 刷新输入流缓冲区（目的是读取并丢弃向量后的换行符）cout << "请输入一个字符串。如 abc 12345   xyz" << endl;cin >> str;cout << str << endl;cout << "\n将数据写入文件 output.txt 中..." << endl;ofstream outfile("output.txt");outfile << v << endl<< str << endl;outfile.close();cout << "\n清除对象的数据..." << endl;v.resize(0);str.resize(0);cout << "向量：" << v << endl<< "字符串：\"" << str << "\"" << endl;cout << "\n从文件 output.txt 中读取的数据：" << endl;ifstream infile("output.txt");infile >> v;infile >> str;infile.close();cout << "向量：" << v << endl<< "字符串：\"" << str << "\"" << endl;return 0;
}

4.3 TestString.cpp

#include "Vec.h"int TestString()
{String str1 = "Hello", str2 = str1, str3;// 转换构造		拷贝构造 	默认构造cout << "原始数据（双引号是另外添加的）：" << endl;cout << "str1 = \"" << str1<< "\"\nstr2 = \"" << str2<< "\"\nstr3 = \"" << str3 << "\"" << endl;str3 = str2;				// 赋值运算str1 = "C++ program.";str2 = str3 + ", world!";	// 拼接运算cout << "str1 = \"" << str1<< "\"\nstr2 = \"" << str2<< "\"\nstr3 = \"" << str3 << "\"" << endl;cout << "\n将数据写入文件 string.txt 中..." << endl;ofstream outfile("string.txt");outfile << str1 << '\n'<< str2 << '\n'<< str3 << endl;outfile.close();cout << "\n清除对象的数据（即调整长度到0）..." << endl;str1.resize(0);str2.resize(0);str3.resize(0);cout << "str1 = \"" << str1<< "\"\nstr2 = \"" << str2<< "\"\nstr3 = \"" << str3 << "\"" << endl;cout << "\n从文件 string.txt 中读取的数据：" << endl;ifstream infile("string.txt");infile >> str1>> str2>> str3;infile.close();cout << "str1 = \"" << str1<< "\"\nstr2 = \"" << str2<< "\"\nstr3 = \"" << str3 << "\"" << endl;cout << "\n异常处理测试" << endl;String str4 = "Hello";try{cout << str4 << endl;cout << str4[10] << endl;//越界访问，抛出异常}catch (const char* str){cout << str << endl;return 0;}return 0;
}

4.4 TestVector.cpp

#include "Vec.h"int TestVector()
{int a[10] = { 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 };double x[8];for (int i = 0; i < 8; i++)x[i] = sqrt(double(i));Vector<int> vi1(10, a), vi2(5, a + 5);Vector<double> vd1(8, x), vd2(3, x);cout << "原始数据：" << endl;cout << "vi1 = " << vi1 << "\nvi2 = " << vi2<< "\nvd1 = " << vd1 << "\nvd2 = " << vd2 << endl;cout << "调整维数到5：" << endl;vi1.resize(5);vi2.resize(5);vd1.resize(5);vd2.resize(5);cout << "vi1 = " << vi1 << "\nvi2 = " << vi2<< "\nvd1 = " << vd1 << "\nvd2 = " << vd2 << endl;cout << "\n将数据写入文件 vector.txt 中..." << endl;ofstream outfile("vector.txt");outfile << vi1 << '\n'<< vi2						<< vd1 << '\n' << vd2 << endl;outfile.close();cout << "\n清除对象的数据(即调整维数到0)..." << endl;vi1.resize(0);vi2.resize(0);vd1.resize(0);vd2.resize(0);cout << "vi1 = " << vi1 << "\nvi2 = " << vi2<< "\nvd1 = " << vd1 << "\nvd2 = " << vd2 << endl;cout << "\n从文件 vector.txt 中读取的数据：" << endl;ifstream infile("vector.txt");infile >> vi1 >> vi2 >> vd1 >> vd2;infile.close();cout << "vi1 = " << vi1 << "\nvi2 = " << vi2<< "\nvd1 = " << vd1 << "\nvd2 = " << vd2 << endl;cout << "\nvi1 + vi2 = " << vi1 + vi2<< "\nvd1 + vd2 = " << vd1 + vd2 << endl;cout << "\n异常处理测试" << endl;Vector<int> v;cout << "请输入一个整数向量。如 (1, 3, 5, 7)" << endl;try{cin >> v;//如果格式错误，则抛出异常}catch (const char* str){cout << str << endl;return 0;}return 0;
}

注意：

包含项目的文件夹中以下三个文本文档需要自行创建：