MultiplyMatric.cpp

/*
C++ program to multiply matrices (two dimensional array), this program multiplies two matrices
which will be entered by the user. Firstly user will enter the order of a matrix.
If the entered orders of two matrix is such that they can't be multiplied then an error message
is displayed on the screen
*/
#include <iostream.h>
#include <conio.h>
 
int main()
{
  int m, n, p, q, c, d, k, sum = 0;
  int first[10][10], second[10][10], multiply[10][10];
 
  cout<<"Enter the number of rows and columns of first matrix\n";
  cin>>m>>n;
  
  cout<<"Enter the elements of first matrix\n";
 
  for (  c = 0 ; c < m ; c++ )
    for ( d = 0 ; d < n ; d++ )
      cin>>first[c][d];
 
  cout<<"Enter the number of rows and columns of second matrix\n";
  cin>>p>>q;
 
  if ( n != p )
    cout<<"Matrices with entered orders can't be multiplied with each other.\n";
  else
  {
    cout<<"Enter the elements of second matrix\n";
 
    for ( c = 0 ; c < p ; c++ )
      for ( d = 0 ; d < q ; d++ )
        cin>>second[c][d];
 
    for ( c = 0 ; c < m ; c++ )
    {
      for ( d = 0 ; d < q ; d++ )
      {
        for ( k = 0 ; k < p ; k++ )
        {
          sum = sum + first[c][k]*second[k][d];
        }
 
        multiply[c][d] = sum;
        sum = 0;
      }
    }
 
    cout<<"Product of entered matrices:-\n";
 
    for ( c = 0 ; c < m ; c++ )
    {
      for ( d = 0 ; d < q ; d++ )
        cout<<" "<<multiply[c][d];
 
      cout<<endl;
    }
  }
 getch();
  return 0;
}