ABS
#define ABS(a) (((a)<0) ? -(a) : (a))
#define ABS(x) (((x) < 0) ? -(x) : (x))
#define ABS(x) (((x) < 0)? -(x) : (x))
#define ABS(x) (((x) < 0)? -(x) : (x))
#define ABS(x) (((x) >= 0) ? (x) : (-(x)))
#define ABS(x) (((x) >= 0) ? (x) : (-(x)))
#define ABS(x) (((x) >= 0) ? (x) : (-(x)))
#define ABS(a) ((a) < 0 ? -(a) : (a))