字符串比较的效率问题[已解决]
本帖最后由 gto250 于 2011-5-11 18:07 编辑$begin = TimerInit()
$a="123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430"
$b="95412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123"
$a1=StringUpper($a)
$b1=StringUpper($b)
For $n=1 To 500
Dim $c
For $i=1 To StringLen($a1) Step 4
$a_1=StringMid($a1,$i,4)
$b_1=StringMid($b1,$i,4)
$d=StringCompare($a_1,$b_1)
If $d=0 Then
$c=$c&"0"
Else
$c=$c&"1"
EndIf
Next
Next
$dif = TimerDiff($begin)
MsgBox(0,"",$dif/1000)
这是我写的代码，循环500次对两个字符串进行比较，每4个字符为1组，相同的设置为1，不同的设置为0
我的机子4G内存 2.6双核
运行时间要8秒左右！
兄弟们有什么好的算法没！ 回复 1# gto250
我认为处理的慢是慢在了从你的$a $b抽取字符上了，我提议把$a $b做成数组进行对比 第三个数组储存结果，最后把数组转换成字符串，你认为可行吗，可行的话 我上代码 本帖最后由 afan 于 2011-4-14 21:24 编辑
直接比对试下$begin = TimerInit()
$a = "123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430"
$b = "95412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123"
$a = StringUpper($a)
$b = StringUpper($b)
Dim $c
For $n = 1 To 500
For $i = 1 To StringLen($a) Step 4
If StringMid($a, $i, 4) == StringMid($b, $i, 4) Then
$c &= "1"
Else
$c &= "0"
EndIf
Next
Next
$dif = TimerDiff($begin)
MsgBox(0, '', $dif / 1000)另外，你上面的“相同的设置为1，不同的设置为0”貌似反了吧 回复 3# afan
大叔你误会我的意思了，他在循环的时候存在重复从一个大的字符串提取字串的过程，我认为慢在这里了，我的意思是用正则一次提取出500个字串 然后$a==$b 存入$c
最后处理数组$c 转化成字符串 本帖最后由 netegg 于 2011-4-14 22:29 编辑
这个最后要什么结果？$begin = TimerInit()
$a = "123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430"
$b = "95412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123"
$a = Stringtobinary($a);_stringtohex()
$b = Stringtobinary($b);_stringtohex()
$c =bitand($a, $b)
$dif = TimerDiff($begin)
MsgBox(0, '', $dif / 1000)大概可以，不过有点小问题。stringtobinary好像有位数限制，思路而已 回复 4# love5173
我那是回的LZ的，没想到你已经在2楼了~
循环500次我想只是便于比较效率而已，并非一次提取500个字符…
我那里简单处理了一下，LZ的要8秒，我的1.2秒 回复 6# afan
的确快了很多，1.2秒左右
再去除
$a = StringUpper($a)
$b = StringUpper($b)
这两句以后，就要1.5S左右了，这是什么原因呢？ 本帖最后由 love5173 于 2011-4-14 22:29 编辑
$begin = TimerInit()
$a="123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430"
$b="95412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123"
$a1=StringUpper($a)
$b1=StringUpper($b)
$aa=StringRegExp($a1,'\w{4}',3)
$bb=StringRegExp($b1,'\w{4}',3)
;_ArrayDisplay ($aa)
For $n=1 To 500
Dim $c
;Global $i
For $i=0 To UBound($aa)-1
;$a_1=StringMid($a1,$i,4)
;$b_1=StringMid($b1,$i,4)
$d=StringCompare($aa[$i],$bb[$i])
If $d=0 Then
$c=$c&"0"
Else
$c=$c&"1"
EndIf
Next
Next
$dif = TimerDiff($begin)
MsgBox(0,"",$dif/1000)这个是我的，貌似也挺慢的，我CPU不行，帮我测试下时间，我的cpu跑下来要21秒，我这cpu什么水平，显示是双核2.5,4G内存，HP笔记本 回复 8# love5173
6.75秒 回复 7# gto250
这个不清楚~ 可能是如果去掉这两行将加重后面 == 比对时的负担~ 没搞明白，lz到底是要比对完的字符串还是就想知道相同与否 本帖最后由 love5173 于 2011-4-14 22:38 编辑
$begin = TimerInit()
$a="123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430123456789012345698765432107654301234567890123456987654321076543012345678901234569876543210765430"
$b="95412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123580125789685469870125493159541235801257896854698701254931595412358012578968546987012549315954123"
$a1=StringUpper($a)
$b1=StringUpper($b)
$aa=StringRegExp($a1,'\w{4}',3)
$bb=StringRegExp($b1,'\w{4}',3)
;_ArrayDisplay ($aa)
For $n=1 To 500
Dim $c
;Global $i
For $i=0 To UBound($aa)-1
;$a_1=StringMid($a1,$i,4)
;$b_1=StringMid($b1,$i,4)
Dim $d
If $aa[$i] == $bb[$i] Then
If $d=0 Then
$c=$c&"0"
Else
$c=$c&"1"
EndIf
EndIf
Next
Next
$dif = TimerDiff($begin)
MsgBox(0,"",$dif/1000)试试这个，偷学大叔的，应该比大叔的快，貌似如果把c换成数组处理能更快 本帖最后由 netegg 于 2011-4-14 22:37 编辑
0.0002秒多点 回复 13# netegg
你用的什么本子啊，我的是HP8510W2.5 双核 ，4G内存 为什么跑起来差距这么大 本帖最后由 netegg 于 2011-4-14 22:43 编辑
用位运算不用比对呀，不管怎么节省条件，读取字符串本身就不是脚本的强项