Multiplication Matrices

Write a program to print matrix multiplication?

This java program multiply two matrices. Before multiplication matrices are checked whether they can be multiplied or not.
Source code of the program:

import java.util.Scanner;

class MatrixMultiplication
{
public static void main(String args[])
{
      int m, n, p, q, sum = 0, c, d, k;

      Scanner in = new Scanner(System.in);
      System.out.println("Enter the number of rows and columns of first matrix");
      m = in.nextInt();
      n = in.nextInt();

      int first[][] = new int[m][n];

      System.out.println("Enter the elements of first matrix");

      for ( c = 0 ; c < m ; c++ )
      for ( d = 0 ; d < n ; d++ )
      first[c][d] = in.nextInt();

      System.out.println("Enter the number of rows and columns of second matrix");
      p = in.nextInt();
      q = in.nextInt();

      if ( n != p )
      System.out.println("Matrices with entered orders can't be multiplied with each other.");
      else
      {
      int second[][] = new int[p][q];
      int multiply[][] = new int[m][q];

      System.out.println("Enter the elements of second matrix");

      for ( c = 0 ; c < p ; c++ )
      for ( d = 0 ; d < q ; d++ )
      second[c][d] = in.nextInt();

      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;
      }
      }

      System.out.println("Product of entered matrices:-");

      for ( c = 0 ; c < m ; c++ )
      {
      for ( d = 0 ; d < q ; d++ )
      System.out.print(multiply[c][d]+"\t");

      System.out.print("\n");
      }
      }
   }
}

Output of the program:

This is a basic method of multiplication, there are more efficient algorithms available. Also this approach is not recommended for sparse matrices which contains a large number of elements as zero.