abs-labs-llabs-abs64.md

title	description	ms.date	api_name	api_location	api_type	topic_type	f1_keywords	helpviewer_keywords
abs, labs, llabs, _abs64	API reference for abs, labs, llabs, and _abs64; which calculates the absolute value of a value.	04/05/2018	abs _abs64 labs llabs	msvcrt.dll msvcr80.dll msvcr90.dll msvcr100.dll msvcr100_clr0400.dll msvcr110.dll msvcr110_clr0400.dll msvcr120.dll msvcr120_clr0400.dll ucrtbase.dll api-ms-win-crt-utility-l1-1-0.dll	DLLExport	apiref	_abs64 STDLIB/_abs64 abs CORECRT_MATH/abs STDLIB/abs CSTDLIB/abs labs CORECRT_MATH/labs llabs CORECRT_MATH/llabs	absolute values abs function abs64 function _abs64 function calculating absolute values

abs, labs, llabs, _abs64

Calculates the absolute value of the argument.

Syntax

intabs( intn ); longlabs( longn ); long longllabs( long longn ); __int64_abs64( __int64n );

longabs( long n ); // C++ onlylonglongabs( longlong n ); // C++ onlydoubleabs( double n ); // C++ onlylongdoubleabs( longdouble n ); // C++ onlyfloatabs( float n ); // C++ only

Parameters

n
Numeric value.

Return value

The abs, labs, llabs, and _abs64 functions return the absolute value of the parameter n. There's no error return.

Remarks

Because C++ allows overloading, you can call overloads of abs that take and return long, long long, float, double, and long double values. These overloads are defined in the <cmath> header. In a C program, abs always takes and returns an int.

Microsoft-specific: The range of negative integers representable in any integral type is larger than the range of positive integers representable in that type. So, it's possible to supply an argument to these functions that can't be converted. If the absolute value of the argument can't be represented by the return type, the abs functions return the argument value unchanged. Specifically, abs(INT_MIN) returns INT_MIN, labs(LONG_MIN) returns LONG_MIN, llabs(LLONG_MIN) returns LLONG_MIN, and _abs64(_I64_MIN) returns _I64_MIN. Effectively, the abs functions can't be used to guarantee a positive value.

Requirements

Routine	Required C header	Required C++ header
abs, labs, llabs	<math.h> or <stdlib.h>	<cmath>, <cstdlib>, <stdlib.h> or <math.h>
_abs64	<stdlib.h>	<cstdlib> or <stdlib.h>

To use the overloaded versions of abs in C++, you must include the <cmath> header.

Example

This program computes and displays the absolute values of several numbers.

// crt_abs.c// Build: cl /W3 /TC crt_abs.c// This program demonstrates the use of the abs function// by computing and displaying the absolute values of// several numbers.#include<stdio.h>#include<math.h>#include<stdlib.h>#include<limits.h>intmain( void ) { intix=-4; longlx=-41567L; long longllx=-9876543210LL; __int64wx=-1; // absolute 32 bit integer valueprintf_s("The absolute value of %d is %d\n", ix, abs(ix)); // absolute long integer valueprintf_s("The absolute value of %ld is %ld\n", lx, labs(lx)); // absolute long long integer valueprintf_s("The absolute value of %lld is %lld\n", llx, llabs(llx)); // absolute 64 bit integer valueprintf_s("The absolute value of 0x%.16I64x is 0x%.16I64x\n", wx, _abs64(wx)); // Integer error cases:printf_s("Microsoft implementation-specific results:\n"); printf_s(" abs(INT_MIN) returns %d\n", abs(INT_MIN)); printf_s(" labs(LONG_MIN) returns %ld\n", labs(LONG_MIN)); printf_s(" llabs(LLONG_MIN) returns %lld\n", llabs(LLONG_MIN)); printf_s(" _abs64(_I64_MIN) returns 0x%.16I64x\n", _abs64(_I64_MIN)); }

The absolute value of -4 is 4 The absolute value of -41567 is 41567 The absolute value of -9876543210 is 9876543210 The absolute value of 0xffffffffffffffff is 0x0000000000000001 Microsoft implementation-specific results: abs(INT_MIN) returns -2147483648 labs(LONG_MIN) returns -2147483648 llabs(LLONG_MIN) returns -9223372036854775808 _abs64(_I64_MIN) returns 0x8000000000000000 

See also

Data conversion
Math and floating-point support
_cabs
fabs, fabsf, fabsl
imaxabs