Defined in header <cstdlib> | ||
---|---|---|
int abs( int n ); | ||
long abs( long n ); | ||
long long abs( long long n ); | (since C++11) | |
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.
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 <iostream> #include <cstdlib> #include <climits> int main() { std::cout << "abs(+3) = " << std::abs(3) << '\n' << "abs(-3) = " << std::abs(-3) << '\n'; // std::cout << abs(INT_MIN)); // undefined behavior on 2's complement systems }
Output:
abs(+3) = 3 abs(-3) = 3
See also
absolute value of a floating point value (|x|) (function) | |
returns the magnitude of a complex number (function template) | |
applies the function std::abs to each element of valarray (function template) | |
C documentation for abs, labs, llabs |
Please login to continue.