$//$ Returns the maximum, minimum, and average area of shapes in the tree

$//$ An empty tree should not modify the maximum, minimum, or average

void max$\_$min$\_$avg$\_$area$($tree$\_$node$\_$t$*$ root, double$*$ max, double$*$ min, double$*$ avg$)$

$\{$

$//$ IMPLEMENT THIS

$\}$