实验三 类与对象
实验任务4:
Vector_int.hpp:
#ifndef VECTOR_INT_HPP #define VECTOR_INT_HPP #include<iostream> using namespace std; class Vector_int{ public: Vector_int(int n); Vector_int(int n, int value); Vector_int(const Vector_int &vector_int); ~Vector_int(); int &at(int index); void show(); private: int size; int *p; }; Vector_int::Vector_int(int n):size(n){ p = new int[size]; for(int i=0; i<size; i++){ p[i] = 0; } } Vector_int::Vector_int(int n, int value):size(n){ p = new int[size]; for(int i=0; i<size; i++){ p[i] = value; } } Vector_int::Vector_int(const Vector_int &vector_int):size(vector_int.size){ p = new int[size]; for(int i=0; i<size; i++){ p[i] = vector_int.p[i]; } } Vector_int::~Vector_int(){ delete[] p; } int &Vector_int::at(int index){ if(index>=0&&index<size){ return p[index]; } } void Vector_int::show(){ for(int i=0; i<size; i++){ cout << p[i] << "\t"; } cout << endl; } #endif
task4.cpp:
#include<iostream> #include "Vector_int.hpp" int main(){ using namespace std; int n,value; cout << "请输入数组大小n:"; cin >> n; cout << "请输入数组初始化特定值value:"; cin >> value; cout << endl; cout << "分别创建数组对象x1,x2,x3如下所示" << endl; cout << endl; Vector_int x1(n); Vector_int x2(n,value); Vector_int x3(x2); x3.at(0) = 999; cout << "数组对象x1为:" << endl; x1.show(); cout << endl; cout << "数组对象x2为:" << endl; x2.show(); cout << endl; cout << "数组对象x3为:" << endl; x3.show(); cout << endl; }
实验任务5:
Matrix.hpp:
#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); // 用pvalue指向的连续内存块数据为矩阵赋值 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 }; // 类Matrix的实现:待补足 Matrix::Matrix(int n):lines(n),cols(n){ p = new double[lines*cols]; for(int i=0; i<lines*cols; i++){ p[i] = 0; } } Matrix::Matrix(int n, int m):lines(n),cols(m){ p = new double[lines*cols]; for(int i=0; i<lines*cols; i++){ p[i] = 0; } } Matrix::Matrix(const Matrix &X):lines(X.lines),cols(X.cols){ p = new double[lines*cols]; for(int i=0; i<lines*cols; i++){ p[i] = X.p[i]; } } Matrix::~Matrix(){ delete[] p; } void Matrix::set(const double *pvalue){ for(int i=0; i<lines*cols; i++){ p[i] = *pvalue++; } } void Matrix::set(int i, int j, int value){ p[i*cols+j] = value; } double &Matrix::at(int i, int j){ return p[i*cols+j]; } double Matrix::at(int i, int j) const { return p[i*cols+j]; } int Matrix::get_lines() const { return lines; } int Matrix::get_cols() const { return cols; } void Matrix::print() const { for(int i=0; i<lines*cols; i++){ if(i%cols == (cols-1)){ cout << p[i] << endl; } else{ cout << p[i] << ", "; } } } #endif
task5.cpp:
#include <iostream> #include "matrix.hpp" int main() { using namespace std; double x[] = {1, 2, 3, 4, 5, 6}; 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; 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); m3.set(0, 0, 999); m3.print(); }