public int vettPi(int i) {

        if (dim - i == 0)
            return -1;
        if (dim - i == 1)
            return i;
        if (dim - 1 == 2)
            if (v[i] > v[i + 1])
                return v[i];
            else
                return v[i + 1];

        if(v[i]+v[i+2]>v[i+1]+v[i+3])
            r[i]=1;
        else if(v[1]+v[i+3]>v[i+1]+v[i+2])
            r[i]=1;
        else r[i+1]=1;

        return(vettPi(i+2));

    }