int sum_odd_leaves(btree t)
{
	if(!tree_empty(t))
	{
		return 0;
	}
	else if((tree_empty(get_left(t)) && tree_empty(get_right(t))) && get_info(t)%2==0)
	{
		return 1;
	}
	return(sum_odd_leaves(get_left(t))+sum_odd_leaves(get_right(t)));
}