Given, $\mathrm{V}=x \cos ^{2} y \hat{i}+x^{2} e^{x} \hat{j}+z \sin ^{2} y \hat{k}$ and $S$ the surface of a unit cube with one corner at the origin and edges parallel to the coordinate axes, the value of the integral $\iint_{\mathrm{S}} \overrightarrow{\mathrm{V}}, \hat{n} d \mathrm{~S}$ is _________.
