Matrix Multiplication using Java

import java.util.Scanner;
class MatrixMultiply {
    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("Resultant matrix after multiplication of two 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");
            }
        }
    }
}