# std::abs, std::labs, std::llabs, std::imaxabs

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< cpp‎ | numeric‎ | math

Defined in header `<cstdlib>` |  |
Defined in header `<cmath>` |  | (since C++17)
int abs( int n ); |  |
long abs( long n ); |  |
long long abs( long long n ); |  | (since C++11)
Defined in header `<cstdlib>` |  |
long labs( long n ); |  |
long long llabs( long long n ); |  | (since C++11)
Defined in header `<cinttypes>` |  |
std::intmax_t abs( std::intmax_t n ); |  | (since C++11)
std::intmax_t imaxabs( std::intmax_t n ); |  | (since C++11)

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

If `std::abs` is called with an argument of type `X` such that std::is_unsigned <X>::value is `true` and `X` cannot be converted to int by integral promotion, the program is ill-formed. | (since C++17)

### 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

Run this code

    #include <iostream>
    #include <cstdlib>
    #include <climits>

    int main()
    {
        std::cout << "abs(+3) = " << std::abs(3) << '\n'
                  << "abs(-3) = " << std::abs(-3) << '\n';

    //  std::cout << std::abs(INT_MIN); // undefined behavior on 2's complement systems
    }

Output:

    abs(+3) = 3
    abs(-3) = 3

### See also

abs(float)fabsfabsffabsl (C++11)(C++11) | absolute value of a floating point value (|x|) (function)
abs(std::complex) | returns the magnitude of a complex number (function template)
abs(std::valarray) | applies the function std::abs to each element of valarray (function template)

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