use fabs() instead of abs()
use fabs() for floating point
n is an integer, use abs()
use fabs() for floating point
use fabs() for floating point
use fabs() for floating point
test of array to null pointer is always false
use correct format specifier
use fabs() for floating point
include missing math.h header
use fabs() for floating point
use cabs() for complex types
use fabsf() instead of abs()