/C

# abs, labs, llabs, imaxabs

Defined in header `<stdlib.h>`
`int        abs( int n );`
`long       labs( long n );`
`long long llabs( long long n );`
(since C99)
Defined in header `<inttypes.h>`
`intmax_t imaxabs( intmax_t n );`
(since C99)

Computes the absolute value of an integer number. The behavior is undefined if the result cannot be represented by the return type.

### Parameters

 n - integer value

### Return value

The absolute value of `n` (i.e. `|n|`), if it is representable.

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 <stdio.h>
#include <stdlib.h>
#include <limits.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
}```

Output:

```abs(+3) = 3
abs(-3) = 3```
• C17 standard (ISO/IEC 9899:2018):
• 7.8.2.1 The imaxabs function (p: 159)
• 7.22.6.1 The abs, labs and llabs functions (p: 259)
• C11 standard (ISO/IEC 9899:2011):
• 7.8.2.1 The imaxabs function (p: 218)
• 7.22.6.1 The abs, labs and llabs functions (p: 356)
• C99 standard (ISO/IEC 9899:1999):
• 7.8.2.1 The imaxabs function (p: 199-200)
• 7.20.6.1 The abs, labs and llabs functions (p: 320)
• C89/C90 standard (ISO/IEC 9899:1990):
• 4.10.6.1 The abs function
• 4.10.6.3 The labs function

 fabsfabsffabsl (C99)(C99) computes absolute value of a floating-point value (\(\small{|x|}\)|x|) (function) cabscabsfcabsl (C99)(C99)(C99) computes the magnitude of a complex number (function) C++ documentation for `abs`