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This document uses PHP Chinese website manual Release
(PHP 5 >= 5.3.0)
SplHeap::compare — Compare elements in order to place them correctly in the heap while sifting up.
$value1
, mixed $value2
)
Compare value1
with value2
.
Throwing exceptions in SplHeap::compare() can corrupt the Heap and place it in a blocked state. You can unblock it by calling SplHeap::recoverFromCorruption() . However, some elements might not be placed correctly and it may hence break the heap-property.
value1
The value of the first node being compared.
value2
The value of the second node being compared.
Result of the comparison, positive integer if value1
is greater than value2
, 0 if they are equal, negative integer otherwise.
Note:
Having multiple elements with the same value in a Heap is not recommended. They will end up in an arbitrary relative position.