abs, _abs64
Calculate the absolute value.
int abs(
int n
);
long abs(
long n
); // C++ only
double abs(
double n
); // C++ only
long double abs(
long double n
); // C++ only
float abs(
float n
); // C++ only
__int64 _abs64(
__int64 n
);
Parameters
- n
Integer value.
Return Value
The abs function returns the absolute value of its parameter. There is no error return.
Remarks
Because C++ allows overloading, you can call overloads of abs. In a C program, abs always takes and returns an int.
注意
Both abs(INT_MIN) and _abs64(INT_MIN) return a value of INT_MIN. Although this is the only time that abs and _abs64 return a negative value, it means that abs and _abs64 cannot be used to guarantee a positive value.
Requirements
Routine |
Required header |
---|---|
abs |
<math.h> |
_abs64 |
<stdlib.h> |
Example
This program computes and displays the absolute values of several numbers.
// crt_abs.c
// This program demonstrates the user of the abs function
// by computing and displaying the absolute values of
// several numbers.
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
int main( void )
{
int ix = -4,
iy;
long lx = -41567L,
ly;
double dx = -3.141593,
dy;
__int64 wx = -1, wy;
// absolute 64 bit integer value
wy = _abs64( wx );
printf_s( "The absolute value of %I64x is %I64x\n", wx, wy);
// absolute 32 bit integer value
iy = abs( ix );
printf_s( "The absolute value of %d is %d\n", ix, iy);
// absolute long integer value
ly = labs( lx );
printf_s( "The absolute value of %ld is %ld\n", lx, ly);
// absolute double value
dy = fabs( dx );
printf_s( "The absolute value of %f is %f\n", dx, dy );
}
The absolute value of ffffffffffffffff is 1 The absolute value of -4 is 4 The absolute value of -41567 is 41567 The absolute value of -3.141593 is 3.141593
.NET Framework Equivalent
See Also
Reference
Change History
Date |
History |
Reason |
---|---|---|
September 2010 |
Added a note about INT_MIN. |
Information enhancement. |