SplHeap::extract
(PHP 5 >= 5.3.0, PHP 7, PHP 8)
SplHeap::extract — Extracts a node from top of the heap and sift up
说明
参数
此函数没有参数。
返回值
The value of the extracted node.
错误/异常
Throws RuntimeException when the data-structure is empty.
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User Contributed Notes 1 note
Sandro Alves Peres ¶
9 years ago
<?php
$heap = new SplMaxHeap(); # Ascending order
$heap->insert('E');
$heap->insert('B');
$heap->insert('D');
$heap->insert('A');
$heap->insert('C');
echo $heap->extract(), PHP_EOL; # E
echo $heap->extract(), PHP_EOL; # D
$heap = new SplMinHeap(); # Descending order
$heap->insert('E');
$heap->insert('B');
$heap->insert('D');
$heap->insert('A');
$heap->insert('C');
print PHP_EOL;
echo $heap->extract(), PHP_EOL; # A
echo $heap->extract(), PHP_EOL; # B
?>