Let $\int \mathrm{x}^{3} \sin x \mathrm{~d} x=\mathrm{g}(x)+\mathrm{C}$, where C is the constant of integration. If $8\left(\mathrm{~g}\left(\frac{\pi}{2}\right)+\mathrm{g}^{\prime}\left(\frac{\pi}{2}\right)\right)=\alpha \pi^{3}+\beta \pi^{2}+\gamma, \alpha, \beta, \gamma \in Z$, then $\alpha+\beta-\gamma$ equals :