$/*$ TODO: implement this function

$*$ Returns $1$ if and only if the board is in a valid Sudoku board state.

$*$ Otherwise returns $0.$

$*$

$*$ A valid row or column contains only blanks or the digits $1-$size,

$*$ with no duplicate digits, where size is the value $1$ to $9.$

$*$

$*$ Note: p$2$A requires only that each row and each column are valid.

$*$

$*$ board: heap allocated $2$D array of integers

$*$ size: number of rows and columns in the board

$*/$

int valid$\_$board$($int $**$board$,$ int size$)\{$

return $0$;

$\}$