# This file have been taken from RevLib (www.revlib.org). 
.i 4
.o 4
.ilb D C B A
.ob D C B A
0000	0001
0001	0010
0010	0011
0011	0100
0100	0101
0101	0110
0110	0111
0111	1000
1000	1001
1001	0000
1010	----
1011	----
1100	----
1101	----
1110	----
1111	----
.e