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Matrix multiplication

rasha Talal (5)
Hi everyone!
I am student and I have started c++ program. I need some help in my assignment( Matrix multiplication ) This is an assignment:
Multiplication of matrices is often used for solving system of equations and for rotation of graphic objects in computer graphics. In this task you will write a program that takes a pair of matrices, multiplies and produces another matrix.
Theory: In the multiplication C = A*B, where A is a m•p-matrix and B is a p•n-matrix, C will then be a m•n-matrix. A condition must be that the number of columns in A = the number of rows in B.
Write a program that multiplies two loaded matrices. The program should at least use the following declarations:
const int MAXDIM = 2;
typedef double Matrix[MAXDIM][MAXDIM];
void readMatrix(Matrix M, int row, int col);
// Reads one matrix with row rows and col columns
void multMatrix(const Matrix A, const Matrix B, Matrix C, int m, int n, int p);
// Multiplies m•p-matrix A with p•n matrix B and stores the result in the m•n-matrix C
void printMatrix(const Matrix M, int row, int col);
// Prints the matrix M
Global variables may not be used! 


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This is my code does not work very well. I have to follow the required rules above in assignment. Please Help!
#include<iostream>
#include<iomanip>
using namespace std;


 const int MAXDIM = 2;
typedef double Matrix[MAXDIM][MAXDIM];

void readMatrix(Matrix M, int row, int col);
void multMatrix( const Matrix A, const Matrix B, Matrix C, int m, int n, int p);
void printMatrix(const Matrix M, int row, int col);

int main()
{
	//double Matrix[MAXDIM][MAXDIM];
	Matrix mat;
	    int rows = 0;
		int cols = 0;
		int i = 0;
		int j = 0;
		int k = 0;
		Matrix a;
		Matrix b;
		Matrix c;
		do
		{
			cout << "Matrix multiplication " << endl
				<< "======================" << endl;
			cout << "Enter dimension of matrix A (row x col) with space between: ";
			cin >> rows >> cols;
		
		} while (rows < 0 || cols < 0 || rows > MAXDIM || cols > MAXDIM);
		
		//cout << "Enter the matrix values A in free format\n";
		cout << "Enter matrix A in free format: \n";
		readMatrix(mat, rows, cols);
	    
		
		  cout << "Enter matrix A in free format : \n";
			//cin >> i >> k;
			for (i = 0; i <MAXDIM; i++)
			{
				for (k = 0; k < MAXDIM; k++)

					cin >> a[i][k];
				cin.ignore(80, '\n');


			}
			cout << "Enter matrix B in free format : \n";
			//cin >> k >> j;
			for (k = 0; k <MAXDIM; k++)
			{
				for (j = 0; j < MAXDIM; j++)

					cin >> b[k][j];
				cin.ignore(80, '\n');
			}

			c[i][j] = (a[i][k] * b[k][j]) + c[i][j];
			multMatrix(a, b, c, i, j, k);
	
	
	
	 cout << "--------------------------------------------------" << endl;
	 cout << "ANSWER IS :" << endl;
		printMatrix(mat, rows, cols);
	return 0;

}
void readMatrix(Matrix M, int row, int col)
{
	for (int r = 0; r < row; ++r)
	{
		for (int c = 0; c < col; ++c)
		
			cin >> M[r][c];
			cin.ignore(80, '\n');
		   
	}
	/*cout << "\n The value of the first matrix A: ";
	for (int r = 0; r < row; ++r)
	{
		cout << "\n";
		for (int c = 0; c < col; ++c)
		{
			cout << M[r][c] << "\t";
		}
	}*/
	cout << endl;
	cout << "Enter dimension of matrix B (row x col) with space between: ";
	cin >> row >> col;
	cout << "Enter matrix B in free format: \n";
	for (int r = 0; r < row; ++r)
	{
		for (int c = 0; c < col; ++c)
			cin >> M[r][c];
		cin.ignore(80, '\n');

	}

	/*cout << "\n The value of the first matrix B: ";
	for (int r = 0; r < row; ++r)
	{
		cout << "\n";
		for (int c = 0; c < col; ++c)
		{
			cout << M[r][c] << "\t";
		}
	}
	cout << endl;*/

}

void multMatrix( const Matrix A,  const Matrix B, Matrix C, int m, int n, int p)
{
	for (m = 0; m < 2; m++)
	{
		for (p = 0; p < 2; p++)
		
			cout << A[m][p] << "\t";
		cin.ignore(80, '\n');
	}
	cout << endl;
	for (p = 0; p < 2; p++)
	{
		for (n = 0; n < 2; n++)
		
			cout << B[p][n] << " \t";
		
		cin.ignore(80, '\n');
	}
	cout << endl;
	if (m==n)
	{
		for ( m = 0; m<2; m++){
			for ( n = 0; n < 2; n++){
				C[m][n] = 0;
				for (p = 0; p < 2; p++)
					C[m][n] = (A[m][p] * B[p][n]) + C[m][n];

			}
		}
	}
	else
	{
		cout << "WRONG!" << endl;
	}
		

	
}

	
void printMatrix(const Matrix M, int row, int col)
{
	for (int r = 0; r < row; ++r) { 
		for (int c = 0; c < col; ++c) 
			cout << setw(16) << M[r][c]; 
		cout << endl; 
	}
	cout << endl;
}

  Put the code you need help with here.
ne555 (10692)
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