我想为主观论文开发测验系统。在这个系统中，用户可以在段落中回答问题，而不是从多项选择中选择。管理员可以添加带有关键字数量的问题作为答案。我想要一个有效的算法来比较用户答案（最多 100 个字）和预定义的关键字数组（最多 50 个字）。我该如何实施？请帮帮我。
提前致谢！ 我正在考虑将用户段落转换为单词数组，而不是与预定义关键字数组进行比较。但我认为这是实施该系统的耗时方法。 例如，如果用户答案数组包含 100 个单词，而预定义数组包含 50 个单词，那么 100*50 比较，这太昂贵了。
请帮我在php中找到有效的解决方案。
【问题讨论】：
标签： php arrays algorithm data-structures logic
如果要将文本拆分为单词，则必须分别为每种语言执行算法。您将面临一个问题，即用空格分隔文本不足以完成您的任务：标点符号仍然存在。所以你必须保存- 并修剪!、,、! 等字符。同时，如果您查看中文，您可能会发现它们使用了另一组标点符号，因此您必须将它们全部枚举。
但是，使用str_word_count 方法和预定义字母的小帮助很容易解决此任务。下面的示例适用于英文文本（没有额外的字母）和希腊文本（有字母）：
function words($string, $charlist = null)
{
return str_word_count($string, 1, $charlist);
}
$string_ASCII = 'ASCII string example'; # string(20) "ASCII string example"
$result = words($string_ASCII); # Array
# (
# [0] => ASCII
# [1] => string
# [2] => example
# )
$string_UTF8 = 'UTF-8 string πράδειγμα'; # string(31) "UTF-8 string πράδειγμα"
$alphabet = '1234567890-ΑΒΓΔΕΖΗΘΙΚΛΜΝΞΟΠΡΣΤΥΦΧΨΩαάβγδεζηθικλμνξοπρστυφχψω';
$result = words($string_UTF8, $alphabet); # Array
# (
# [0] => UTF-8
# [1] => string
# [2] => πράδειγμα
# )
$keywords = array_flip($keywords); # $keywords - your 50 words
$words = words($string); # $string - a text with 100 words from user
foreach ($words as $word)
{
# only 100 iterations with fast isset validation
if (isset($keywords[$word]))
{
# it exists!
}
}
leg 时，用户可能会使用legs，这也是正确的。对于英语，我可能会推荐下一个代码：# Author - https:#gist.github.com/tbrianjones
# Source - https:#gist.github.com/tbrianjones/ba0460cc1d55f357e00b
#
# The MIT License (MIT)
#
# Copyright (c) 2015
#
#
# Changes:
# Removed rule for virus -> viri
# Added rule for potato -> potatoes
# Added rule for *us -> *uses
class english
{
private static $plural = array
(
'/(quiz)$/i' => '$1zes',
'/^(ox)$/i' => '$1en',
'/([m|l])ouse$/i' => '$1ice',
'/(matr|vert|ind)ix|ex$/i' => '$1ices',
'/(x|ch|ss|sh)$/i' => '$1es',
'/([^aeiouy]|qu)y$/i' => '$1ies',
'/(hive)$/i' => '$1s',
'/(?:([^f])fe|([lr])f)$/i' => '$1$2ves',
'/(shea|lea|loa|thie)f$/i' => '$1ves',
'/sis$/i' => 'ses',
'/([ti])um$/i' => '$1a',
'/(tomat|potat|ech|her|vet)o$/i' => '$1oes',
'/(bu)s$/i' => '$1ses',
'/(alias)$/i' => '$1es',
'/(octop)us$/i' => '$1i',
'/(ax|test)is$/i' => '$1es',
'/(us)$/i' => '$1es',
'/s$/i' => 's',
'/$/' => 's'
);
private static $singular = array
(
'/(quiz)zes$/i' => '$1',
'/(matr)ices$/i' => '$1ix',
'/(vert|ind)ices$/i' => '$1ex',
'/^(ox)en$/i' => '$1',
'/(alias)es$/i' => '$1',
'/(octop|vir)i$/i' => '$1us',
'/(cris|ax|test)es$/i' => '$1is',
'/(shoe)s$/i' => '$1',
'/(o)es$/i' => '$1',
'/(bus)es$/i' => '$1',
'/([m|l])ice$/i' => '$1ouse',
'/(x|ch|ss|sh)es$/i' => '$1',
'/(m)ovies$/i' => '$1ovie',
'/(s)eries$/i' => '$1eries',
'/([^aeiouy]|qu)ies$/i' => '$1y',
'/([lr])ves$/i' => '$1f',
'/(tive)s$/i' => '$1',
'/(hive)s$/i' => '$1',
'/(li|wi|kni)ves$/i' => '$1fe',
'/(shea|loa|lea|thie)ves$/i' => '$1f',
'/(^analy)ses$/i' => '$1sis',
'/((a)naly|(b)a|(d)iagno|(p)arenthe|(p)rogno|(s)ynop|(t)he)ses$/i' => '$1$2sis',
'/([ti])a$/i' => '$1um',
'/(n)ews$/i' => '$1ews',
'/(h|bl)ouses$/i' => '$1ouse',
'/(corpse)s$/i' => '$1',
'/(us)es$/i' => '$1',
'/s$/i' => ''
);
private static $irregular = array
(
'move' => 'moves',
'foot' => 'feet',
'goose' => 'geese',
'sex' => 'sexes',
'child' => 'children',
'man' => 'men',
'tooth' => 'teeth',
'person' => 'people'
);
private static $uncountable = array
(
'sheep',
'fish',
'deer',
'series',
'species',
'money',
'rice',
'information',
'equipment'
);
public static function pluralize($string)
{
# save some time in the case that singular and plural are the same
if (in_array(mb_strtolower($string), self::$uncountable))
{
return $string;
}
# check for irregular singular forms
foreach (self::$irregular as $pattern => $result)
{
$pattern = '/' . $pattern . '$/i';
if (preg_match($pattern, $string))
{
return preg_replace($pattern, $result, $string);
}
}
# check for matches using regular expressions
foreach (self::$plural as $pattern => $result)
{
if (preg_match($pattern, $string))
{
return preg_replace($pattern, $result, $string);
}
}
return $string;
}
public static function singularize($string)
{
# save some time in the case that singular and plural are the same
if (in_array(mb_strtolower($string), self::$uncountable))
{
return $string;
}
# check for irregular plural forms
foreach (self::$irregular as $result => $pattern)
{
$pattern = '/' . $pattern . '$/i';
if (preg_match($pattern, $string))
{
return preg_replace($pattern, $result, $string);
}
}
# check for matches using regular expressions
foreach (self::$singular as $pattern => $result)
{
if (preg_match($pattern, $string))
{
return preg_replace($pattern, $result, $string);
}
}
return $string;
}
}
$words = array_unique($words)（如果您的关键字列表中有legs并且用户使用它100次，它可能会解决问题）获得 100 分）。此外，它会使您的代码更快一点，因为更少的单词 = 更少的循环中的迭代 :)【讨论】：
检查复杂度为O(number_of_unique_answer_keywords * log(keywords) * avg(string_length))。
【讨论】：
使用 PHP 中的 levenshtein 或 similar_text 函数来比较两个数组的精确匹配和接近匹配
【讨论】：