#ifndef __vector_int_HPP__
#define __vector_int_HPP__
#include<iostream>
#include<cassert>
using namespace std;
class Vector_int
{
public:
Vector_int() {};
Vector_int(int n);
Vector_int(int n, int a);
Vector_int(const Vector_int& x);
~Vector_int();
void print();
int& at(int x);
private:
int size;
int* p;
};
Vector_int::Vector_int(int n):size(n)
{
p = new int[size];
for (auto i = 0; i < size; i++)
{
p[i] = 0;
}
}
Vector_int::Vector_int(int n, int a):size(n)
{
p = new int[size];
for (int i = 0; i < size; i++)
{
p[i] = a;
}
}
Vector_int::Vector_int(const Vector_int& x) :size(x.size)
{
cout << "deep copy" << endl;
p = new int[size];
for (auto i = 0; i < size; i++)
{
p[i] = x.p[i];
}
}
Vector_int::~Vector_int()
{
cout << "deleting......." << endl;
delete[] p;
}
void Vector_int::print()
{
int i;
for (i = 0; i < size; i++)
{
cout << p[i] <<" ";
}
}
int& Vector_int::at(int x)
{
assert(x >= 0 && x < size);
return p[x];
}
#endif // !__vector_int_HPP__
#include"vector_int.hpp"
#include<iostream>
using namespace std;
int main()
{
int n,u;
cout << "print n:";
cin >> n;
Vector_int z(n); // 创建一个动态大小的int型数组对象x,向系统申请n个int型数据项
z.print();
cout << endl;
Vector_int x(n, 6); // 创建一个动态大小的int型数组对象x,向系统申请n个int型数据项
x.print();
Vector_int y(x); // 用已经存在的对象x构造新的对象y
cout << "print u:";
cin >> u;
y.at(u) = 99;
y.print();
}
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#ifndef MATRIX_H
#define MATRIX_H
#include <iostream>
#include <cassert>
using namespace std;
class Matrix
{
public:
Matrix(int n); // 构造函数,构造一个n*n的矩阵
Matrix(int n, int m); // 构造函数,构造一个n*m的矩阵
Matrix(const Matrix& X); // 复制构造函数,使用已有的矩阵X构造
~Matrix(); //析构函数
void set(const double* pvalue);
void set(int i, int j, int value); //设置矩阵第i行第j列元素值为value
double& at(int i, int j); //返回矩阵第i行第j列元素的引用
double at(int i, int j) const; // 返回矩阵第i行第j列元素的值
int get_lines() const; //返回矩阵行数
int get_cols() const; //返回矩列数
void print() const; // 按行打印输出矩阵
private:
int lines; // 矩阵行数
int cols; // 矩阵列数
double* p; // 指向存放矩阵数据的内存块的首地址
};
Matrix::Matrix(int n):lines(n),cols(n)
{
p = new double[n * n];
}
Matrix::Matrix(int n, int m):lines(n),cols(m)
{
p = new double[n * m];
}
Matrix::Matrix(const Matrix& X):lines(X.lines),cols(X.cols)
{
p = new double[lines * cols];
for (auto i = 0; i < lines * cols; i++)
{
p[i] = X.p[i];
}
}
Matrix::~Matrix()
{
delete[] p;
}
void Matrix::set(const double* pvalue)
{
for (auto i = 0; i < lines * cols; i++)
{
p[i] = pvalue[i];
}
}
void Matrix::set(int i, int j, int value)
{
assert(i >= 0 && i < lines&& j >= 0 && j < cols);
p[i * cols + j] = value;
}
double& Matrix::at(int i, int j)
{
assert(i >= 0 && i < lines&& j >= 0 && j < cols);
return p[i * cols + j];
}
double Matrix::at(int i, int j) const
{
assert(i >= 0 && i < lines&& j >= 0 && j < cols);
return p[i * cols + j];
}
int Matrix::get_lines() const
{
return lines;
}
int Matrix::get_cols() const
{
return cols;
}
void Matrix::print()const
{
for (auto i = 0; i < lines; i++)
{
for (auto j = 0; j < cols; j++)
{
cout << p[i * cols + j] << " ";
}
cout << endl;
}
}
#endif
#include <iostream>
#include "matrix.hpp"
int main()
{
using namespace std;
double x[] = { 1, 2, 3, 7, 8, 9 };
Matrix m1(3, 2); // 创建一个3×2的矩阵
m1.set(x); // 用一维数组x的值按行为矩阵m1赋值
m1.print(); // 打印矩阵m1的值
cout << "the first line is: " << endl;
cout << m1.at(0, 0) << " " << m1.at(0, 1) << endl; // 输出矩阵m1第1行两个
cout << endl;
Matrix m2(2, 3);
m2.set(x);
m2.print();
cout << "the first line is: " << endl;
cout << m2.at(0, 0) << " " << m2.at(0, 1) << " " << m2.at(0, 2) << endl;
cout << endl;
Matrix m3(m2); // 用矩阵m2构造新的矩阵m3
m3.set(0, 2, 99); // 将矩阵m3第0行第0列元素值设为999
m3.print();
}
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