/**
* Análise infix
* @param TreeNode $treeNode
* @return string String da expressão
*/
private function showInFixNode($treeNode)
{
$output = '';
if ($treeNode != null) {
if ($treeNode instanceof TreeNode) {
$output .= "( ";
}
$output .= $this->showInFixNode($treeNode->getLeft());
$output .= "{$treeNode->toString()} ";
$output .= $this->showInFixNode($treeNode->getRight());
if ($treeNode instanceof TreeNode) {
$output .= ") ";
}
}
return $output;
}
