Help with Matrix Multiplication

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#include <iostream>
#include <math.h>
using namespace std;
	
class Row 
{

	double *arrArray;
	int nLength;
public:
			
	 Row()
	 {
	 }
	 Row(int length)
	 {
		 this->nLength = length;
		 this->arrArray = new double[length];

		 for (int i = 0; i < length; i++)
		 {
			cout << "Enter your number: " << endl;
			cin >> arrArray[i];
		 }
	 }
	 Row(int length, double* arr)
	 {
		 this->nLength = length;
		 this->arrArray = arr;
	 }

	 // Get
	 int GetLength ()
	 {
		 return (this->nLength);
	 }

	 double* GetArray()
	 {
		 return (this->arrArray);
	 }

	// Set
	 void SetLength(int length)
	 {
		 this->nLength = length;
	 }

	 void SetArray(double* arr)
	 {
		 this->arrArray = arr;
	 }

	 const double operator[](int Index) const
	 {
		 return (this->arrArray)[Index];
	 }
	 const Row operator+(const Row rRow) const
	 {
		 for (int i = 0; i < this->nLength; i++)
		 {
			 (this->arrArray)[i] += rRow[i];
		 }

		 return Row(rRow.nLength, this->arrArray);
	 }
	 const Row operator-(const Row rRow) const
	 {
		 for (int i = 0; i < this->nLength; i++)
		 {
			 (this->arrArray)[i] -= rRow[i];
		 }

		 return Row(rRow.nLength, this->arrArray);
	 }
     const Row operator*(const Row rRow) const
	 {
		 for (int i = 0; i < this->nLength; i++)
		 {
			 (this->arrArray)[i] *= rRow[i];
		 }

		 return Row(rRow.nLength, this->arrArray);
	 }
	 const bool operator==(const Row rRow) const
	 {
		 bool bAreEqual = true;
		 for (int i = 0; i < this->nLength; i++)
		 {
			 if (rRow[i] != (this->arrArray)[i])
			 {
				 bAreEqual = false;
			 }
		 }

		 return (bAreEqual);
	 }
	 const Row operator=(Row rRow) const
	 {
		 for (int i = 0; i < this->nLength; i++)
		 {
			 this->arrArray[i] = rRow.GetArray()[i];
		 }

		 return Row(rRow.nLength, this->arrArray);
	 }
	 void operator++() const
	 {
		 for (int i = 0; i < this->nLength; i++)
		 {
			 (this->arrArray)[i] += 1;
		 }
	 }
	 void operator--() const
	 {
		 for (int i = 0; i < this->nLength; i++)
		 {
			 (this->arrArray)[i] -= 1;
		 }
	 }
	 void operator!() const
	 {
		 for (int i = 0; i < this->nLength; i++)
		 {
			 (this->arrArray)[i] *= (-1);
		 }
	 }
	 void PrintRow()
	 {
		 for(int i=0;i < this->nLength; i++)
		 {
			 cout << this->arrArray[i] << ", ";
		 }
		 cout << endl;
	 }
	 

};

class Matrix
{
	int nCols;
	Row *mMatrix;

public:

	Matrix()
	{

	}
	Matrix(int cols, Row* matrix)
	{
		this->nCols = cols;
		this->mMatrix = matrix;
	}
	// Get
	 int GetLength ()
	 {
		 return (this->nCols);
	 }

	 Row* GetArray()
	 {
		 return (this->mMatrix);
	 }

	// Set
	 void SetLength(int length)
	 {
		 this->nCols = length;
	 }

	 void SetArray(Row* matrix)
	 {
		 this->mMatrix = matrix;
	 }


	 const Row operator[](int Index) const
	 {
		 return (this->mMatrix)[Index];
	 }
	 const Matrix operator+(const Matrix mMat) const
	 {
		 if (this->nCols != mMat.nCols)
		 {
			 cout << "לא ניתן לבצע את הפעולה" << endl;
		 }
		 else
		 {
			for (int i = 0; i < this->nCols; i++)
			{
				for (int j = 0; j < this->mMatrix[0].GetLength(); j++)
				{
					(this->mMatrix[i]).GetArray()[j] += mMat[i][j];
				}
			}
		 }
		 return Matrix(this->nCols, this->mMatrix);
	 }
	 

	 //Matrix operator*(Matrix mMat) 
	 //{
		//
		// if ((this->mMatrix[1].GetLength() == mMat.nCols))
		// {
		//	 Matrix NewMatrix((this->mMatrix)->GetLength(), mMat.GetArray()->GetLength());

		//	 for (int i = 0; i < mMat.nCols; i++)
		//	 {
		//		for (int j = 0; j< mMat.nCols; j++)
		//		{
		//			for (int inner = 0; inner < this->GetLength(); inner++)
		//			{
		//				//NewMatrix.GetArray()[i].GetArray()[j] = (this[i][inner] * mMat[inner][j]);
		//			}
		//		}
		//	 }
		// }

		// else if ((mMat.GetArray()[0].GetLength()))
		// {
		// }
		// else
		// {
		//	 cout << "לא ניתן לבצע את הפעולה" << endl;
		// }
		// return Matrix(this->nCols, this->mMatrix);
	 //}

	 /*
	 void MultilpyMatrix()
	 {
		 for (int i = 0; i < this->nCols; i++)
		 {
			 for (int j = 0; j < this->mMatrix[0].GetLength(); j++)
			 {
				 //this->mMatrix[i].GetArray()[j]=mMat[i][j]
				 this->mMatrix[i][j]=

					 (matrix1[j]*matrix2[j])+(matrix1[j+1]*matrix2[j+1])+(matrix1[j+2]*matrix2[j+2])
				 
			 }
		 }
	 }
	 */
	 void PrintMatrix()
	 {
		 for(int i=0;i < this->nCols; i++)
		 {
			 for(int j=0;j < this->mMatrix[0].GetLength(); j++)
			 {
				 cout << this->GetArray()[i][j] << ", ";
			 }
			 cout << endl;
		 }
		 cout << endl;
	 }
};

void main()
{
	
	/*
	Row a(2);
	Row b(2);

	Row* maarah = new Row[2];
	maarah[0] = a;
	maarah[1] = b;
    
	Matrix mat(2, maarah);

	*/
	//Checking:
	Row Row1(5);
	Row Row2(5);
	
	Row1=Row1+Row2;
	cout << "Sum Rows: \n";
	Row1.PrintRow();

	Row1=Row1-Row2;
	cout << "Substract Rows: \n";
	Row1.PrintRow();

	Row1=Row1*Row2;
	cout << "Multiply Rows: \n";
	Row1.PrintRow();

	Row1++;
	cout << "Operator ++: \n" ;
	Row1.PrintRow();

	Row1--;
	cout << "Operator --: \n";
	Row1.PrintRow();

	!Row1;
	cout << "Operator !: \n";
	Row1.PrintRow();



	Row* maarah = new Row[2];
	maarah[0] = Row1;
	maarah[1] = Row2;

	cout << endl << endl;

	//Matrix Mat2(2, 5);
	//Matrix Mat1(2, maarah);
	//Mat1.PrintMatrix();

	//Mat1*Mat2;
	//cout << mat[1][1] << endl;


};


I need to override * in Matrix class and do a matrix multiplication.
Any suggeststions?

Thank!
to overwrite, use "&" in the function definition.
void my_function(int &my_variable);
for the matrix multiplication check wikipedia.
But it works without "&"...
guess you are using global variables then. that also works
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