Let [t] denote the greatest integer less than or equal to t. Let f:[0, ∞) → R be a function defined by f(x)=[x/2+3]-[√ x ]. Let S be the set of all…

Let $\displaystyle [t]$ denote the greatest integer less than or equal to t . Let $\displaystyle f:[0, \infty) \rightarrow \mathrm{R}$ be a function defined by $\displaystyle f(x)=\left[\frac{x}{2}+3\right]-[\sqrt{x}]$. Let $\displaystyle S$ be the set of all points in the interval $\displaystyle [0,8]$ at which $\displaystyle f$ is not continuous. Then $\displaystyle \sum_{\mathrm{a} \in \mathrm{S}} \mathrm{a}$ is equal to $\displaystyle \_\_\_\_$.