/* svuk002@ec.auckland.ac.nz */

class MMul {

	/*
	 *  Your task is to complete the matrixMultiply method below.
	 *  
	 *  Here is the pseudocode:
	 *
	 *  define matrixMultiply (A, B):
	 *    { Multiply two n by n matrices and store the product in matrix C }
	 *    
	 *    Construct matrix C
	 *
	 *    for each row i of C:
	 *      for each column j of C:
	 *        sumSoFar = 0
	 *		  for each k in [1..n]:
	 *          sumSoFar = sumSoFar + Entry of A at (i, k) x
	 *                          Entry of B at (k, j)
	 *        Entry of C at (i, j) = sumSoFar
	 *
	 *    return C
	 */

	static int[][] matrixMultiply (int[][] a, int[][] b) {
	/* You need to complete this method */
		return null;
	}
	
	static void testCaseOne () {
	/* A simple test case */
		int[][] a = {{2, -1}, {1, 3}};
		int[][] b = {{1, 1},{0, -1}};
		
		int[][] c = matrixMultiply (a, b);
		
		String result = "2 3\n1 -2";
		System.out.print ("Test Case One:\n\n");
		System.out.print ("The result should be:\n" + result);
		System.out.print ("\nYour result is:\n" + printMatrix (c) + "\n");
	}
	
	static void testCaseTwo () {
	/* Another simple test case */
		int[][] a = {{10, -19, 34}, {1, 3, 23}, {67, 45, -9}};
		int[][] b = {{14, 21, -9}, {0, -1, 16}, {58, 3, -8}};
		
		int[][] c = matrixMultiply (a, b);
		
		String result = "2112 331 -666\n1348 87 -145\n416 1335 189";
		System.out.print ("Test Case Two:\n\n");
		System.out.print ("The result should be:\n" + result);
		System.out.print ("\nYour result is:\n" + printMatrix (c) + "\n");
	}
	
	static String printMatrix (int[][] c) {
	/* Print matrix c to a string */ 
		String toRet = "";
		for (int i = 0; i < c.length; i++) {
			for (int j = 0; j < c[i].length; j++)
				toRet += c[i][j] + " ";
			toRet += "\n";
		}
		return toRet;
	}
	
	public static void main (String[] args) {
	/* 
	 *  Entry point.
	 *  You can test your matrixMultiply () method by uncommenting
	 *  the test cases below.
	 *
	 */
		//testCaseOne ();
		//testCaseTwo ();
	}
	
}