/*FUNCTION<<abs>>---integer absolute value (magnitude)INDEX	absANSI_SYNOPSIS	#include <stdlib.h>	int abs(int <[i]>);TRAD_SYNOPSIS	#include <stdlib.h>	int abs(<[i]>)	int <[i]>;DESCRIPTION<<abs>> returns@tex$|x|$,@end texthe absolute value of <[i]> (also called the magnitudeof <[i]>).  That is, if <[i]> is negative, the result is the oppositeof <[i]>, but if <[i]> is nonnegative the result is <[i]>.The similar function <<labs>> uses and returns <<long>> rather than <<int>> values.RETURNSThe result is a nonnegative integer.PORTABILITY<<abs>> is ANSI.No supporting OS subroutines are required.*/#include <stdlib.h>int_DEFUN (abs, (i), int i){  return (i < 0) ? -i : i;}