Hell, I wanted to excercise the mind, here's a class to add, subtract and multiply matrices :D
class matrix {
public static void main(String[] args) {
int[][] matrix1 = {{2,1},{1,3},{2,3},{4,2}};
int[][] matrix2 = {{1,3,2,1}};
int[][] matrix3 = {{-2,1},{-3,3},{2,-3},{14,2}}...