abs, labs, llabs, imaxabs
Header: <stdlib.h>
Computes the absolute value of an integer number. The behavior is undefined if the result cannot be represented by the return type.
# Declarations
int abs( int n );
long labs( long n );
long long llabs( long long n );
(since C99)
intmax_t imaxabs( intmax_t n );
(since C99)
# Parameters
n: integer value
# Return value
The absolute value of n (i.e. |n|), if it is representable.
# Notes
In 2’s complement systems, the absolute value of the most-negative value is out of range, e.g. for 32-bit 2’s complement type int, INT_MIN is -2147483648, but the would-be result 2147483648 is greater than INT_MAX, which is 2147483647.
# Example
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
int main(void)
{
printf("abs(+3) = %d\n", abs(+3));
printf("abs(-3) = %d\n", abs(-3));
// printf("%+d\n", abs(INT_MIN)); // undefined behavior on 2's complement systems
}