row 0: (0, 4)  (1, -1)  (4, -1) 
row 1: (0, -1)  (1, 4)  (2, -1)  (5, -1) 
row 2: (1, -1)  (2, 4)  (3, -1)  (6, -1) 
row 3: (2, -1)  (3, 4)  (7, -1) 
row 4: (0, -1)  (4, 4)  (5, -1)  (8, -1) 
row 5: (1, -1)  (4, -1)  (5, 4)  (6, -1)  (9, -1) 
row 6: (2, -1)  (5, -1)  (6, 4)  (7, -1)  (10, -1) 
row 7: (3, -1)  (6, -1)  (7, 4)  (11, -1) 
row 8: (4, -1)  (8, 4)  (9, -1)  (12, -1) 
row 9: (5, -1)  (8, -1)  (9, 4)  (10, -1)  (13, -1) 
row 10: (6, -1)  (9, -1)  (10, 4)  (11, -1)  (14, -1) 
row 11: (7, -1)  (10, -1)  (11, 4)  (15, -1) 
row 12: (8, -1)  (12, 4)  (13, -1) 
row 13: (9, -1)  (12, -1)  (13, 4)  (14, -1) 
row 14: (10, -1)  (13, -1)  (14, 4)  (15, -1) 
row 15: (11, -1)  (14, -1)  (15, 4) 
writing matrix in binary to matrix.dat ...
reading matrix in binary from matrix.dat ...
row 0: (0, 4)  (1, -1)  (4, -1) 
row 1: (0, -1)  (1, 4)  (2, -1)  (5, -1) 
row 2: (1, -1)  (2, 4)  (3, -1)  (6, -1) 
row 3: (2, -1)  (3, 4)  (7, -1) 
row 4: (0, -1)  (4, 4)  (5, -1)  (8, -1) 
row 5: (1, -1)  (4, -1)  (5, 4)  (6, -1)  (9, -1) 
row 6: (2, -1)  (5, -1)  (6, 4)  (7, -1)  (10, -1) 
row 7: (3, -1)  (6, -1)  (7, 4)  (11, -1) 
row 8: (4, -1)  (8, 4)  (9, -1)  (12, -1) 
row 9: (5, -1)  (8, -1)  (9, 4)  (10, -1)  (13, -1) 
row 10: (6, -1)  (9, -1)  (10, 4)  (11, -1)  (14, -1) 
row 11: (7, -1)  (10, -1)  (11, 4)  (15, -1) 
row 12: (8, -1)  (12, 4)  (13, -1) 
row 13: (9, -1)  (12, -1)  (13, 4)  (14, -1) 
row 14: (10, -1)  (13, -1)  (14, 4)  (15, -1) 
row 15: (11, -1)  (14, -1)  (15, 4)