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abs, _abs64

Updated: September 2010

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 


Integer value.

The abs function returns the absolute value of its parameter. There is no error return.

C++ allows overloading, so you can call overloads of abs. In a C program, abs always takes and returns an int.

Caution noteCaution:

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.


Required header





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,
    long    lx = -41567L,
    double  dx = -3.141593,
    __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




September 2010

Added a note about INT_MIN.

Information enhancement.

Community Additions

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