PowerShell中两个以上字符串的最长公共子字符串?
如何在PowerShell中的字符串数组中找到匹配的字符串: 例如:PowerShell中两个以上字符串的最长公共子字符串?,powershell,Powershell,如何在PowerShell中的字符串数组中找到匹配的字符串: 例如: $Arr = "1 string first", "2 string second", "3 string third", "4 string fourth" 使用此示例,我希望返回以下内容: " string " 我想用它来查找文件名的匹配部分,然后删除该部分文件名(例如,从一组mp3文件中删除艺术家的姓名),而不必指定手动替换文件名的哪一部分。如果我理解您的问题: $Arr = "1 string first", "2
$Arr = "1 string first",
"2 string second",
"3 string third",
"4 string fourth"
使用此示例,我希望返回以下内容:
" string "
我想用它来查找文件名的匹配部分,然后删除该部分文件名(例如,从一组mp3文件中删除艺术家的姓名),而不必指定手动替换文件名的哪一部分。如果我理解您的问题:
$Arr = "1 string first", "2 string second", "3 string third", "4 string fourth"
$Arr -match " string " | foreach {$_ -replace " string ", " "}
如果它(艺术家姓名等)只是一个单词:
$Arr = "1 string first", "2 string second", "3 string third", "4 string fourth"
$common = $Arr | %{ $_.split() } | group | sort -property count | select -last 1 | select -expand name
$common = " {0} " -f $common
更新:
似乎适用于多个单词的实现(查找单词的最长公共子字符串):
下面是PowerShell中两个字符串的“最长公共子字符串”函数(基于wikibooks):
若要将其用于两个以上的字符串,请如下使用:
Function get-LongestCommonSubstringArray
{
Param(
[Parameter(Position=0, Mandatory=$True)][Array]$Array
)
$PreviousSubString = $Null
$LongestCommonSubstring = $Null
foreach($SubString in $Array)
{
if($LongestCommonSubstring)
{
$LongestCommonSubstring = get-LongestCommonSubstring $SubString $LongestCommonSubstring
write-verbose "Consequtive diff: $LongestCommonSubstring"
}else{
if($PreviousSubString)
{
$LongestCommonSubstring = get-LongestCommonSubstring $SubString $PreviousSubString
write-verbose "first one diff: $LongestCommonSubstring"
}else{
$PreviousSubString = $SubString
write-verbose "No PreviousSubstring yet, setting it to: $PreviousSubString"
}
}
}
Return $LongestCommonSubstring
}
get-LongestCommonSubstringArray $Arr -verbose
- 生成InputString的所有唯一子字符串的列表
- 筛选出现次数为#InputString的子字符串(即在所有输入字符串中)
- 根据子字符串的长度对这些已过滤的子字符串进行排序
- 返回此列表的最后一个(即最长的)
$shortest=$arr | sort Length | select-first 1
),以及2)按长度顺序生成子字符串:$Length..1 | foreach{$l=$0..$Length-$l)| foreach{$shortest.Substring(${,$l)}}其中{@($arr-match[regex]::Escape($})).Count-eq$arr.Count}选择-first 1
Function get-LongestCommonSubstring
{
Param(
[string]$String1,
[string]$String2
)
if((!$String1) -or (!$String2)){Break}
# .Net Two dimensional Array:
$Num = New-Object 'object[,]' $String1.Length, $String2.Length
[int]$maxlen = 0
[int]$lastSubsBegin = 0
$sequenceBuilder = New-Object -TypeName "System.Text.StringBuilder"
for ([int]$i = 0; $i -lt $String1.Length; $i++)
{
for ([int]$j = 0; $j -lt $String2.Length; $j++)
{
if ($String1[$i] -ne $String2[$j])
{
$Num[$i, $j] = 0
}else{
if (($i -eq 0) -or ($j -eq 0))
{
$Num[$i, $j] = 1
}else{
$Num[$i, $j] = 1 + $Num[($i - 1), ($j - 1)]
}
if ($Num[$i, $j] -gt $maxlen)
{
$maxlen = $Num[$i, $j]
[int]$thisSubsBegin = $i - $Num[$i, $j] + 1
if($lastSubsBegin -eq $thisSubsBegin)
{#if the current LCS is the same as the last time this block ran
[void]$sequenceBuilder.Append($String1[$i]);
}else{ #this block resets the string builder if a different LCS is found
$lastSubsBegin = $thisSubsBegin
$sequenceBuilder.Length = 0 #clear it
[void]$sequenceBuilder.Append($String1.Substring($lastSubsBegin, (($i + 1) - $lastSubsBegin)))
}
}
}
}
}
return $sequenceBuilder.ToString()
}
Function get-LongestCommonSubstringArray
{
Param(
[Parameter(Position=0, Mandatory=$True)][Array]$Array
)
$PreviousSubString = $Null
$LongestCommonSubstring = $Null
foreach($SubString in $Array)
{
if($LongestCommonSubstring)
{
$LongestCommonSubstring = get-LongestCommonSubstring $SubString $LongestCommonSubstring
write-verbose "Consequtive diff: $LongestCommonSubstring"
}else{
if($PreviousSubString)
{
$LongestCommonSubstring = get-LongestCommonSubstring $SubString $PreviousSubString
write-verbose "first one diff: $LongestCommonSubstring"
}else{
$PreviousSubString = $SubString
write-verbose "No PreviousSubstring yet, setting it to: $PreviousSubString"
}
}
}
Return $LongestCommonSubstring
}
get-LongestCommonSubstringArray $Arr -verbose
$arr = "qdfbsqds", "fbsqdt", "bsqda"
$arr | %{
$substr = for ($s = 0; $s -lt $_.length; $s++) {
for ($l = 1; $l -le ($_.length - $s); $l++) {
$_.substring($s, $l);
}
}
$substr | %{$_.toLower()} | select -unique
} | group | ?{$_.count -eq $arr.length} | sort {$_.name.length} | select -expand name -l 1
# returns bsqd