Sensitive word substitution algorithm, 4 times times higher efficiency than str_replace (with 6 thousand sensitive words)

Efficiency comparison(12,688 characters, replace 1 times): Str_replace: 0.109937906265 seconds STRTR: 0.0306839942932 seconds Comparison of replacement results For example: "Zhang San", "Zhang San Feng", "Zhangsanfungtan" are prohibited words (why there is such a distinction?) See also "FA x", "" FA xgong") " I'm driving Zhangsanfungtan to work today." strtr:" I'm going to work today with * * * * (all four words replaced for *) str_replace:" I'm driving to work today." (replace only the first match) So using str_replace substitution is not an essential solution to the problem. Time Comparison: Number of keywords: 6712 (no Duplicates) Self init:0.00789093971252 (load XCache) self:0.0354378223419 strtr:0.0311169624329 strtr_array:0. 432713985443 str_replace:0.109627008438 Require (' badword.src.php '); $badword 1 = array_combine ($badword, Array_fill (0,count ($badword), ' * ')); $BB = ' I am driving Zhangsanfungtan to work today '; $str = Strtr ($BB, $badword 1); Copy Code Interested friends can look into the Function Strtr_array (& $str,& $replace _arr) { $maxlen = 0; $minlen = 1024*128; if (Empty ($replace _arr)) return $str; foreach ($replace _arr as $k = + $v) { $len = strlen ($k); if ($len < 1) continue; if ($len > $maxlen) $maxlen = $len; if ($len < $minlen) $minlen = $len; } $len = strlen ($STR); $pos = 0; $result = "; while ($pos < $len) { if ($pos + $maxlen > $len) $maxlen = $len-$pos; $found = false; $key = "; for ($i = 0; $i < $maxlen; + + $i) $key. = $str [$i + $pos]; Original: memcpy (key,str+ $pos, $maxlen) for ($i = $maxlen; $i >= $minlen;--$i) { $key 1 = substr ($key, 0, $i); Original: key[$i] = ' + ' if (Isset ($replace _arr[$key 1])) { $result. = $replace _arr[$key 1]; $pos + = $i; $found = true; Break } } if (! $found) $result. = $str [$pos + +]; } return $result; } Copy Code

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