<?php $priorityQueue = new SplPriorityQueue(); var_dump($priorityQueue->getExtractFlags()); $priorityQueue->insert("a", 1); $priorityQueue->insert("b", 2); $priorityQueue->insert("c", 0); echo "EXTR DEFAULT", PHP_EOL; echo "value: ", $priorityQueue->top(), PHP_EOL; $priorityQueue->setExtractFlags(SplPriorityQueue::EXTR_PRIORITY); var_dump($priorityQueue->getExtractFlags() & SplPriorityQueue::EXTR_PRIORITY); echo "EXTR_PRIORITY", PHP_EOL; echo "priority: ", $priorityQueue->top(), PHP_EOL; $priorityQueue->setExtractFlags(SplPriorityQueue::EXTR_BOTH); echo "EXTR_BOTH", PHP_EOL; print_r($priorityQueue->top()); echo "EXTR_DATA", PHP_EOL; $priorityQueue->setExtractFlags(SplPriorityQueue::EXTR_DATA); echo "value: ", $priorityQueue->top(), PHP_EOL;