#include <stdio.h>
#include <stdlib.h>
#include <math.h>

double *function(double a[2], double b[2])
{
   static double result[2];

   result[0] = a[0]-b[0];
   result[1] = a[1]+b[1];

   return result;
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
int main()
{
    double y[2];
    double *x = &y;
    double z[2];
    double *w = &z;

    z[0] = 3;
    z[1] = 2;

    x = function(z,z);
    w = function(x,z);

    printf("\n (%lf ; %lf)",x[0],x[1]);
    return 0;
}