老生常谈PHP中的数据结构:DS扩展
PHP7以上才能安装和使用该数据结构扩展，安装比较简单：
1.运行命令peclinstallds
2.在php.ini中添加extension=ds.so
3.重启PHP或重载配置
CollectionInterface：包含本库中所有数据结构通用功能的基本interface。Itguaranteesthatallstructuresaretraversable,countable,andcanbeconvertedtojsonusingjson_encode().
Ds\CollectionimplementsTraversable,Countable,JsonSerializable{
/*方法*/
abstractpublicvoidclear(void)
abstractpublicDs\Collectioncopy(void)
abstractpublicboolisEmpty(void)
abstractpublicarraytoArray(void)
}
HashableInterface：whichallowsobjectstobeusedaskeys.
Ds\Hashable{
/*方法*/
abstractpublicboolequals(object$obj)
abstractpublicmixedhash(void)
}
SequenceInterface：ASequence相当于一个一维的数字key数组,withtheexceptionofafewcharacteristics:
Valueswillalwaysbeindexedas[0,1,2,…,size-1].
Onlyallowedtoaccessvaluesbyindexintherange[0,size-1].
Usecases：
Whereveryouwoulduseanarrayasalist(notconcernedwithkeys).
AmoreefficientalternativetoSplDoublyLinkedListandSplFixedArray.
VectorClass：Vector是自动增长和收缩的连续缓冲区中的一系列值。它是最有效的顺序结构，值的索引直接映射到缓冲区中索引，增长因子不绑定到特定的倍数或指数。其具有以下优缺点：
Supportsarraysyntax(squarebrackets).
Useslessoverallmemorythananarrayforthesamenumberofvalues.
Automaticallyfreesallocatedmemorywhenitssizedropslowenough.
Capacitydoesnothavetobeapowerof2.
get(),set(),push(),pop()areallO(1).
但是shift(),unshift(),insert()andremove()areallO(n).
Ds\Vector::allocate—Allocatesenoughmemoryforarequiredcapacity. Ds\Vector::apply—Updatesallvaluesbyapplyingacallbackfunctiontoeachvalue. Ds\Vector::capacity—Returnsthecurrentcapacity. Ds\Vector::clear—Removesallvalues. Ds\Vector::__construct—Createsanewinstance. Ds\Vector::contains—Determinesifthevectorcontainsgivenvalues. Ds\Vector::copy—Returnsashallowcopyofthevector. Ds\Vector::count—Returnsthenumberofvaluesinthecollection. Ds\Vector::filter—Createsanewvectorusingacallabletodeterminewhichvaluestoinclude. Ds\Vector::find—Attemptstofindavalue'sindex. Ds\Vector::first—Returnsthefirstvalueinthevector. Ds\Vector::get—Returnsthevalueatagivenindex. Ds\Vector::insert—Insertsvaluesatagivenindex. Ds\Vector::isEmpty—Returnswhetherthevectorisempty Ds\Vector::join—Joinsallvaluestogetherasastring. Ds\Vector::jsonSerialize—ReturnsarepresentationthatcanbeconvertedtoJSON. Ds\Vector::last—Returnsthelastvalue. Ds\Vector::map—Returnstheresultofapplyingacallbacktoeachvalue. Ds\Vector::merge—Returnstheresultofaddingallgivenvaluestothevector. Ds\Vector::pop—Removesandreturnsthelastvalue. Ds\Vector::push—Addsvaluestotheendofthevector. Ds\Vector::reduce—Reducesthevectortoasinglevalueusingacallbackfunction. Ds\Vector::remove—Removesandreturnsavaluebyindex. Ds\Vector::reverse—Reversesthevectorin-place. Ds\Vector::reversed—Returnsareversedcopy. Ds\Vector::rotate—Rotatesthevectorbyagivennumberofrotations. Ds\Vector::set—Updatesavalueatagivenindex. Ds\Vector::shift—Removesandreturnsthefirstvalue. Ds\Vector::slice—Returnsasub-vectorofagivenrange. Ds\Vector::sort—Sortsthevectorin-place. Ds\Vector::sorted—Returnsasortedcopy. Ds\Vector::sum—Returnsthesumofallvaluesinthevector. Ds\Vector::toArray—Convertsthevectortoanarray. Ds\Vector::unshift—Addsvaluestothefrontofthevector.
DequeClass：“双端队列”的缩写，也用于Ds\Queue中，拥有head、tail两个指针。Thepointerscan“wraparound”theendofthebuffer,whichavoidstheneedtomoveothervaluesaroundtomakeroom.Thismakesshiftandunshiftveryfast — somethingaDs\Vectorcan'tcompetewith.其具有以下优缺点：
Supportsarraysyntax(squarebrackets).
Useslessoverallmemorythananarrayforthesamenumberofvalues.
Automaticallyfreesallocatedmemorywhenitssizedropslowenough.
get(),set(),push(),pop(),shift(),andunshift()areallO(1).
但Capacitymustbeapowerof2.insert()andremove()areO(n).
MapClass：键值对的连续集合，几乎与数组相同。键可以是任何类型，但必须是唯一的。如果使用相同的键添加到map中，则将替换值。其拥有以下优缺点：
Keysandvaluescanbeanytype,includingobjects.
Supportsarraysyntax(squarebrackets).
Insertionorderispreserved.
Performanceandmemoryefficiencyisverysimilartoanarray.
Automaticallyfreesallocatedmemorywhenitssizedropslowenough.
Can'tbeconvertedtoanarraywhenobjectsareusedaskeys.
PairClass：ApairisusedbyDs\Maptopairkeyswithvalues.
Ds\PairimplementsJsonSerializable{
/*方法*/
public__construct([mixed$key[,mixed$value]])
}
SetClass：唯一值序列。ThisimplementationusesthesamehashtableasDs\Map,wherevaluesareusedaskeysandthemappedvalueisignored.其拥有以下优缺点：
Valuescanbeanytype,includingobjects.
Supportsarraysyntax(squarebrackets).
Insertionorderispreserved.
Automaticallyfreesallocatedmemorywhenitssizedropslowenough.
add(),remove()andcontains()areallO(1).
但Doesn'tsupportpush(),pop(),insert(),shift(),orunshift().get()isO(n)iftherearedeletedvaluesinthebufferbeforetheaccessedindex,O(1)otherwise.
StackClass：“lastin,firstout”集合，只允许在结构顶部进行访问和迭代。
Ds\StackimplementsDs\Collection{
/*方法*/
publicvoidallocate(int$capacity)
publicintcapacity(void)
publicvoidclear(void)
publicDs\Stackcopy(void)
publicboolisEmpty(void)
publicmixedpeek(void)
publicmixedpop(void)
publicvoidpush([mixed$...values])
publicarraytoArray(void)
}
QueueClass：“firstin,firstout”集合，只允许在结构前端进行访问和迭代。
Ds\QueueimplementsDs\Collection{
/*Constants*/
constintMIN_CAPACITY=8;
/*方法*/
publicvoidallocate(int$capacity)
publicintcapacity(void)
publicvoidclear(void)
publicDs\Queuecopy(void)
publicboolisEmpty(void)
publicmixedpeek(void)
publicmixedpop(void)
publicvoidpush([mixed$...values])
publicarraytoArray(void)
}
PriorityQueueClass：优先级队列与队列是非常相似的，但值以指定的优先级被推入队列，优先级最高的值总是位于队列的前面，同优先级元素“先入先出”顺序任然保留。在一个PriorityQueue上递代是具有破坏性的，相当于连续弹出操作直到队列为空。Implementedusingamaxheap.
Ds\PriorityQueueimplementsDs\Collection{
/*Constants*/
constintMIN_CAPACITY=8;
/*方法*/
publicvoidallocate(int$capacity)
publicintcapacity(void)
publicvoidclear(void)
publicDs\PriorityQueuecopy(void)
publicboolisEmpty(void)
publicmixedpeek(void)
publicmixedpop(void)
publicvoidpush(mixed$value,int$priority)
publicarraytoArray(void)
}
以上这篇老生常谈PHP中的数据结构:DS扩展就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持毛票票。