Write a function that checks whether the diagonal joining the upper$-$left and the lower$-$right corners of a tic$-$tac$-$toe board are all the same. #include

using namespace std;

$/**$

Return true if all elements on the diagonal joining the upper$-$left

and the lower$-$right corners all the same.

@param board a $3$ x $3$ array of String

@return true if all elements are the same.

$*/$

bool upper$\_$left$\_$to$\_$lower$\_$right$($string board$[3][3])$

$\{$

return $/*$ Your code goes here $*/$ ;

$\}$