Lab2_new

#include <iostream>
#include <clocale>

using namespace std;

class Tmatrix
{
private:
    int n, m;
    int **matrix;

public:
    Tmatrix(int newn, int newm)
    {
        matrix = new int*[newm];
        for(int i=0;i<newm;i++)
            matrix[i] = new int[newn];

        for(int i=0;i<newn;i++)
            for(int j=0;j<newm;j++)
                this->matrix[i][j] = 0;

        n = newn;
        m = newm;
    }

    Tmatrix(){}
    int printMatrix()
    {
        for(int i=0;i<this->n;i++)
        {
            for(int j=0;j<this->m;j++)
                cout<<this->matrix[i][j]<<" ";
            cout<<endl;
        }
        cout<<endl;
        return 0;
    }

    int getElem(int i, int j)
    {
        if(i<this->n && j<this->m)
            return this->matrix[i][j];
        else
            return -1;
    }

    int setElem(int i, int j, int elem)
    {
        if(i<this->n && j<this->m)
        {
            this->matrix[i][j] = elem;
            return 0;
        }
        else
            return -1;
    }


    int fillMatrix()
    {
        for(int i=0;i<this->n;i++)
            for(int j=0;j<this->m;j++)
                this->matrix[i][j] = rand() % 10;
        return 0;
    }

    int getN()
    {
        return n;
    }

    int getM()
    {
        return m;
    }

    Tmatrix* sum(Tmatrix* sumB)
    {
        if(this->n==sumB->getN() && this->m==sumB->getM())
        {
            Tmatrix* resSum = new Tmatrix(this->n,this->m);
            for(int i=0;i<this->n;i++)
                for(int j=0;j<this->m;j++)
                    resSum->setElem(i,j,this->matrix[i][j]+sumB->getElem(i,j));
            return resSum;
        }else
            return NULL;
    }

    Tmatrix* neg(Tmatrix* negB)
    {
        if(this->n==negB->getN() && this->m==negB->getM())
        {
            Tmatrix* resNeg = new Tmatrix(this->n,this->m);
            for(int i=0;i<this->n;i++)
                for(int j=0;j<this->m;j++)
                    resNeg->setElem(i,j,this->matrix[i][j]-negB->getElem(i,j));
            return resNeg;
        }else
            return NULL;
    }

    Tmatrix* mult(Tmatrix* multB)
    {
        if(this->n==multB->getM() && this->m==multB->getN())
        {
            Tmatrix* resMult = new Tmatrix(this->n, multB->getM());
            int premult;
            for(int i=0; i<this->n;i++)
                for(int j=0; j<multB->getM();j++)
                    for(int k=0; k<this->m;k++)
                    {
                        premult = resMult->getElem(i,j);
                        resMult->setElem(i, j, premult+this->matrix[i][k] * multB->getElem(k,j));
                    }
            return resMult;
        }else
            return NULL;
    }

    friend ostream &operator<<(ostream &stream, Tmatrix* obj);
    friend istream &operator>>(istream &stream, Tmatrix** obj);

    ~Tmatrix()
    {
        for(int i=0;i<n;i++)
            delete[] matrix[i];
        delete[] matrix;
    }
};


ostream &operator<<(ostream &stream, Tmatrix* obj)
{
    for(int i=0;i<obj->n;i++)
    {
        for(int j=0;j<obj->m;j++)
            stream<<obj->matrix[i][j]<<" ";
        stream<<endl;
    }
    stream<<endl;

    return stream;
}

istream &operator>>(istream &stream, Tmatrix** obj)
{
    int N,M;
    cout<<"Введите размерность матрицы"<<endl;
    cout<<"N=";
    cin>>N;
    cout<<"M=";
    cin>>M;
    *obj = new Tmatrix(N,M);
    cout<<"Введите матрицу"<<endl;
    for(int i=0;i<(*obj)->n;i++)
        for(int j=0;j<(*obj)->m;j++)
            cin>>(*obj)->matrix[i][j];
    return stream;
}

int main()
{
    setlocale(LC_ALL,"RU");

    Tmatrix* A;
    Tmatrix* B;
    cin>>&A;
    cout<<A;

    cin>>&B;
    cout<<B;

    Tmatrix* sumC;
    Tmatrix* negC;
    Tmatrix* multC;
    sumC = A->sum(B);
    negC = A->neg(B);
    multC = A->mult(B);

    if(sumC!=NULL)
    {
        cout<<"Сумма матриц А и В:"<<endl;
        sumC->printMatrix();
    }else
        cout<<"Суммирование невозможно"<<endl;

    if(negC!=NULL)
    {
        cout<<"Разность матриц А и В:"<<endl;
        negC->printMatrix();
    }else
        cout<<"Вычитание невозможно"<<endl;

    if(multC!=NULL)
    {
        cout<<"Произведение матриц A и B"<<endl;
        multC->printMatrix();
    }else
        cout<<"Умножение невозможно"<<endl;
    system("pause");
    return 0;
}