#define SIGN(a) ((a) < 0 ? -1 : ((a) > 0 ? 1 : 0))
#endif
+#ifndef ODD
+#define ODD(a) (((a) & 1) == 1)
+#endif
+
+#ifndef EVEN
+#define EVEN(a) (((a) & 1) == 0)
+#endif
+
#define SIZEOF_ARRAY(array, type) (sizeof(array) / sizeof(type))
#define SIZEOF_ARRAY_INT(array) SIZEOF_ARRAY(array, int)