#include "header.h"

int
fn(Vector *pv, int call)
{
    static int calls = 1;      // count function calls
    Vector v;
    int size, i;
    float *arr, result; 

    v       = *pv;
    size    = v.n;
    arr     = v.p;
    result  = 0.0;

    // compute sum 
    for(i = 1; i < size - 1; i++)
    {
        float x, lx, nx;
        x  = arr[i];
        nx = arr[i+1];
        lx = arr[i-1];
        result += sin(x*nx + cos(lx - x));
    }
   //check to print the number of calls or the value of function
    if(call == 1)
    {
        printf("%d\n", calls);
    }
    else
        printf("%f\n", result);

    calls++;

    return EXIT_SUCCESS;
}