$22)$ Function Object Class Usage

HomeworkUnanswered

Given the following Sum function object class:

class Sum $\{$ double sum; public: Sum$($double s $=0\mathrm{.}0)$ : sum$\{$s$\}\{\}//$ create double operator$()($double num$)\{$ return sum $+=$ num; $\}//$ update double operator$()($void$)$ const $\{$ return sum; $\}//$ access double reset$($double s $=0\mathrm{.}0)\{$ swap$($sum$,$ s$)$; return s; $\}//[$re$]$initialize $\}$;

Show how to use it to calculate the average of the elements in the following array. $($What kind of loop would be most appropriate here?$)($The declarations are normative; the initializations are illustrative.$)$

const size$\_$t MAX$\{50\}$; long a$[$MAX$]=\{10,14,12,8,10,6,9,13,7,11\}$; size$\_$t num$\_$as$\{10\}$;