C program to perform addition of matrices using functions?

Answer 1

#include<iostream>

#include<iomanip>

#include<vector>

#include<string>

#include<sstream>

using namespace std;

const unsigned width = 4;

const unsigned height = 3;

class matrix

{

private:

vector< vector<unsigned> > m_data;

string m_title;

public:

matrix(string title=""): m_data(height, vector<unsigned>(width)), m_title(title) {}

matrix(const matrix& copy): m_data(copy.m_data), m_title(copy.m_title) {}

matrix& operator=(matrix rhs)

{

// Note: assignment does not overwrite the matrix title.

for(unsigned row=0; row<height; ++row)

for(unsigned col=0; col<width; ++col)

operator[](row)[col]=rhs[row][col];

return(*this);

}

vector<unsigned>& operator[](const unsigned index){return(m_data[index]);}

void set_title(const string title){ m_title = title; }

string& get_title(){return(m_title);}

void show()

{

cout<<m_title<<'\n'<<endl;

for(unsigned row=0; row<height; ++row)

{

for(unsigned col=0; col<width; ++col)

cout<<setw(7)<<(*this)[row][col];

cout<<endl;

}

cout<<endl;

}

matrix& operator+=(matrix rhs)

{

for(unsigned row=0; row<height; ++row)

for(unsigned col=0; col<width; ++col)

(*this)[row][col]+=rhs[row][col];

return(*this);

}

matrix operator+(matrix rhs)

{

matrix result(m_title+" + "+rhs.m_title);

for(unsigned row=0; row<height; ++row)

for(unsigned col=0; col<width; ++col)

result[row][col]=(*this)[row][col]+rhs[row][col];

return(result);

}

matrix& operator-=(matrix rhs)

{

for(unsigned row=0; row<height; ++row)

for(unsigned col=0; col<width; ++col)

(*this)[row][col]-=rhs[row][col];

return(*this);

}

matrix operator-(matrix rhs)

{

matrix result(m_title+" - "+rhs.m_title);

for(unsigned row=0; row<height; ++row)

for(unsigned col=0; col<width; ++col)

result[row][col]=operator[](row)[col]-rhs[row][col];

return(result);

}

};

unsigned input_num (std::string prompt)

{

unsigned id = 0;

while (1)

{

cout<<prompt<<": ";

string input="";

getline (cin, input);

stringstream ss (input);

if (ss>>id)

break;

cout<<"Invalid input.\n";

}

return (id);

}

void initialise(matrix& m)

{

for(unsigned row=0; row<height; ++row)

{

for(unsigned col=0; col<width; ++col)

{

stringstream ss;

ss<<"Enter a value for "<<m.get_title()<<'['<<row<<"]["<<col<<']';

m[row][col]=input_num(ss.str());

}

}

cout<<endl;

}

int main()

{

matrix matrix_1("matrix_1");

initialise(matrix_1);

matrix_1.show();

matrix matrix_2("matrix_2");

initialise(matrix_2);

matrix_2.show();

matrix matrix_3 = matrix_1 + matrix_2;

matrix_3.show();

matrix matrix_4 = matrix_3 - matrix_2;

matrix_4.show();

}