#include
#include
#include
using namespace std;
double average( int, ... );
int main()
{
double w = 3.5, x = 2.5, y = 1.7, z = 1.2;
cout << setiosflags( ios::fixed | ios::showpoint )
<< setprecision( 1 ) << "w = " << w << "\nx = " << x
<< "\ny = " << y << "\nz = " << z << endl;
cout << setprecision( 3 ) << "\nThe average of w and x is "
<< average( 2, w, x )
<< "\nThe average of w, x, and y is "
<< average( 3, w, x, y )
<< "\nThe average of w, x, y, and z is "
<< average( 4, w, x, y, z ) << endl;
return 0;
}
double average( int i, ... )
{
double total = 0;
va_list ap;
va_start( ap, i );
for ( int j = 1; j <= i; j++ )
total += va_arg( ap, double );
va_end( ap );
return total / i;
}