{"id":655,"date":"2006-08-23T18:56:31","date_gmt":"2006-08-23T06:56:31","guid":{"rendered":""},"modified":"2006-08-23T18:56:31","modified_gmt":"2006-08-23T06:56:31","slug":"","status":"publish","type":"post","link":"https:\/\/www.mudone.com\/?p=655","title":{"rendered":"php\u6b63\u5219\u8868\u8fbe\u5f0f"},"content":{"rendered":"

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\n\u610f\u4e49\uff1a\u5339\u914d\u2019x\u2019\u6216\u8005\u2019y\u2019\u3002
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\n\u5b57\u7b26{ n, }
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\u5b57\u7b26{ n,m }
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\u5b57\u7b26[^xyz]
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\u5b57\u7b26b
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\n\u4f8b\u5982\uff1a\/bnw\/\u5339\u914d"noonday"\u4e2d\u7684\u2019no\u2019\uff0c\/wyb\/\u5339\u914d"possibly yesterday."\u4e2d\u7684\u2019ly\u2019\u3002 <\/p>\n

\u5b57\u7b26B
\n\u610f\u4e49\uff1a\u5339\u914d\u4e00\u4e2a\u5355\u8bcd\u7684\u975e\u5206\u754c\u7ebf
\n\u4f8b\u5982\uff1a\/wBn\/\u5339\u914d"noonday"\u4e2d\u7684\u2019on\u2019\uff0c\/yBw\/\u5339\u914d"possibly yesterday."\u4e2d\u7684\u2019ye\u2019\u3002 <\/p>\n

\u5b57\u7b26cX
\n\u610f\u4e49\uff1a\u8fd9\u91cc\u7684X\u662f\u4e00\u4e2a\u63a7\u5236\u5b57\u7b26\u3002\u5339\u914d\u4e00\u4e2a\u5b57\u7b26\u4e32\u7684\u63a7\u5236\u5b57\u7b26\u3002
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\u5b57\u7b26d
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\n\u4f8b\u5982\uff1a\/d\/\u6216\/[0-9]\/\u5339\u914d"B2 is the suite number."\u4e2d\u7684\u20192\u2019\u3002 <\/p>\n

\u5b57\u7b26D
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\n\u4f8b\u5982\uff1a\/D\/\u6216\/[^0-9]\/\u5339\u914d"B2 is the suite number."\u4e2d\u7684\u2019B\u2019\u3002 <\/p>\n

\u5b57\u7b26f
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\n\u4f8b\u5982\uff1a\/sw*\/\u5339\u914d"foo bar."\u4e2d\u7684\u2019 bar\u2019\u3002 <\/p>\n

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\n\u4f8b\u5982\uff1a\/S\/w*\u5339\u914d"foo bar."\u4e2d\u7684\u2019foo\u2019\u3002 <\/p>\n

\u5b57\u7b26t
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\u5b57\u7b26w
\n\u610f\u4e49\uff1a\u5339\u914d\u6240\u6709\u7684\u6570\u5b57\u548c\u5b57\u6bcd\u4ee5\u53ca\u4e0b\u5212\u7ebf\uff0c\u7b49\u4ef7\u4e8e[A-Za-z0-9_]\u3002
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\u5b57\u7b26W
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\u5b57\u7b26n
\n\u610f\u4e49\uff1a\u8fd9\u91cc\u7684n\u662f\u4e00\u4e2a\u6b63\u6574\u6570\u3002\u5339\u914d\u4e00\u4e2a\u6b63\u5219\u8868\u8fbe\u5f0f\u7684\u6700\u540e\u4e00\u4e2a\u5b50\u4e32\u7684n\u7684\u503c(\u8ba1\u6570\u5de6\u5706\u62ec\u53f7)\u3002 <\/p>\n

\u4f8b\u5982\uff1a\/apple(,)sorange1\/\u5339\u914d"apple, orange, cherry, peach."\u4e2d\u7684\u2019apple, orange\u2019\uff0c\u4e0b\u9762\u6709\u4e00\u4e2a\u66f4\u52a0\u5b8c\u6574\u7684\u4f8b\u5b50\u3002
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\n\u610f\u4e49\uff1a\u8fd9\u91cc\u7684ooctal\u662f\u4e00\u4e2a\u516b\u8fdb\u5236\u7684escape\u503c\uff0c\u800cxhex\u662f\u4e00\u4e2a\u5341\u516d\u8fdb\u5236\u7684escape\u503c\uff0c\u5141\u8bb8\u5728\u4e00\u4e2a\u6b63\u5219\u8868\u8fbe\u5f0f\u4e2d\u5d4c\u5165ASCII\u7801 <\/p>\n

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\n\u5c06\u4e0b\u4e00\u4e2a\u5b57\u7b26\u6807\u8bb0\u4e3a\u4e00\u4e2a\u7279\u6b8a\u5b57\u7b26\u3001\u6216\u4e00\u4e2a\u539f\u4e49\u5b57\u7b26\u3001\u6216\u4e00\u4e2a \u540e\u5411\u5f15\u7528\u3001\u6216\u4e00\u4e2a\u516b\u8fdb\u5236\u8f6c\u4e49\u7b26\u3002\u4f8b\u5982\uff0c'n' \u5339\u914d\u5b57\u7b26 "n"\u3002' ' \u5339\u914d\u4e00\u4e2a\u6362\u884c\u7b26\u3002\u5e8f\u5217 '' \u5339\u914d "" \u800c "(" \u5219\u5339\u914d "("\u3002
\n^ \u5339\u914d\u8f93\u5165\u5b57\u7b26\u4e32\u7684\u5f00\u59cb\u4f4d\u7f6e\u3002\u5982\u679c\u8bbe\u7f6e\u4e86 RegExp \u5bf9\u8c61\u7684 Multiline \u5c5e\u6027\uff0c^ \u4e5f\u5339\u914d ' ' \u6216 ' ' \u4e4b\u540e\u7684\u4f4d\u7f6e\u3002
\n$ \u5339\u914d\u8f93\u5165\u5b57\u7b26\u4e32\u7684\u7ed3\u675f\u4f4d\u7f6e\u3002\u5982\u679c\u8bbe\u7f6e\u4e86RegExp \u5bf9\u8c61\u7684 Multiline \u5c5e\u6027\uff0c$ \u4e5f\u5339\u914d ' ' \u6216 ' ' \u4e4b\u524d\u7684\u4f4d\u7f6e\u3002
\n* \u5339\u914d\u524d\u9762\u7684\u5b50\u8868\u8fbe\u5f0f\u96f6\u6b21\u6216\u591a\u6b21\u3002\u4f8b\u5982\uff0czo* \u80fd\u5339\u914d "z" \u4ee5\u53ca "zoo"\u3002 * \u7b49\u4ef7\u4e8e{0,}\u3002
\n+ \u5339\u914d\u524d\u9762\u7684\u5b50\u8868\u8fbe\u5f0f\u4e00\u6b21\u6216\u591a\u6b21\u3002\u4f8b\u5982\uff0c'zo+' \u80fd\u5339\u914d "zo" \u4ee5\u53ca "zoo"\uff0c\u4f46\u4e0d\u80fd\u5339\u914d "z"\u3002+ \u7b49\u4ef7\u4e8e {1,}\u3002
\n? \u5339\u914d\u524d\u9762\u7684\u5b50\u8868\u8fbe\u5f0f\u96f6\u6b21\u6216\u4e00\u6b21\u3002\u4f8b\u5982\uff0c"do(es)?" \u53ef\u4ee5\u5339\u914d "do" \u6216 "does" \u4e2d\u7684"do" \u3002? \u7b49\u4ef7\u4e8e {0,1}\u3002
\n{n} n \u662f\u4e00\u4e2a\u975e\u8d1f\u6574\u6570\u3002\u5339\u914d\u786e\u5b9a\u7684 n \u6b21\u3002\u4f8b\u5982\uff0c'o{2}' \u4e0d\u80fd\u5339\u914d "Bob" \u4e2d\u7684 'o'\uff0c\u4f46\u662f\u80fd\u5339\u914d "food" \u4e2d\u7684\u4e24\u4e2a o\u3002
\n{n,} n \u662f\u4e00\u4e2a\u975e\u8d1f\u6574\u6570\u3002\u81f3\u5c11\u5339\u914dn \u6b21\u3002\u4f8b\u5982\uff0c'o{2,}' \u4e0d\u80fd\u5339\u914d "Bob" \u4e2d\u7684 'o'\uff0c\u4f46\u80fd\u5339\u914d "foooood" \u4e2d\u7684\u6240\u6709 o\u3002'o{1,}' \u7b49\u4ef7\u4e8e 'o+'\u3002'o{0,}' \u5219\u7b49\u4ef7\u4e8e 'o*'\u3002
\n{n,m} m \u548c n \u5747\u4e3a\u975e\u8d1f\u6574\u6570\uff0c\u5176\u4e2dn <= m\u3002\u6700\u5c11\u5339\u914d n \u6b21\u4e14\u6700\u591a\u5339\u914d m \u6b21\u3002\u5218\uff0c "o{1,3}" \u5c06\u5339\u914d "fooooood" \u4e2d\u7684\u524d\u4e09\u4e2a o\u3002'o{0,1}' \u7b49\u4ef7\u4e8e 'o?'\u3002\u8bf7\u6ce8\u610f\u5728\u9017\u53f7\u548c\u4e24\u4e2a\u6570\u4e4b\u95f4\u4e0d\u80fd\u6709\u7a7a\u683c\u3002
\n? \u5f53\u8be5\u5b57\u7b26\u7d27\u8ddf\u5728\u4efb\u4f55\u4e00\u4e2a\u5176\u4ed6\u9650\u5236\u7b26 (*, +, ?, {n}, {n,}, {n,m}) \u540e\u9762\u65f6\uff0c\u5339\u914d\u6a21\u5f0f\u662f\u975e\u8d2a\u5a6a\u7684\u3002\u975e\u8d2a\u5a6a\u6a21\u5f0f\u5c3d\u53ef\u80fd\u5c11\u7684\u5339\u914d\u6240\u641c\u7d22\u7684\u5b57\u7b26\u4e32\uff0c\u800c\u9ed8\u8ba4\u7684\u8d2a\u5a6a\u6a21\u5f0f\u5219\u5c3d\u53ef\u80fd\u591a\u7684\u5339\u914d\u6240\u641c\u7d22\u7684\u5b57\u7b26\u4e32\u3002\u4f8b\u5982\uff0c\u5bf9\u4e8e\u5b57\u7b26\u4e32 "oooo"\uff0c'o+?' \u5c06\u5339\u914d\u5355\u4e2a "o"\uff0c\u800c 'o+' \u5c06\u5339\u914d\u6240\u6709 'o'\u3002
\n. \u5339\u914d\u9664 " " \u4e4b\u5916\u7684\u4efb\u4f55\u5355\u4e2a\u5b57\u7b26\u3002\u8981\u5339\u914d\u5305\u62ec ' ' \u5728\u5185\u7684\u4efb\u4f55\u5b57\u7b26\uff0c\u8bf7\u4f7f\u7528\u8c61 '[. ]' \u7684\u6a21\u5f0f\u3002
\n(pattern) \u5339\u914dpattern \u5e76\u83b7\u53d6\u8fd9\u4e00\u5339\u914d\u3002\u6240\u83b7\u53d6\u7684\u5339\u914d\u53ef\u4ee5\u4ece\u4ea7\u751f\u7684 Matches \u96c6\u5408\u5f97\u5230\uff0c\u5728VBScript \u4e2d\u4f7f\u7528 SubMatches \u96c6\u5408\uff0c\u5728JScript \u4e2d\u5219\u4f7f\u7528 {CONTENT}\u2026 \u5c5e\u6027\u3002\u8981\u5339\u914d\u5706\u62ec\u53f7\u5b57\u7b26\uff0c\u8bf7\u4f7f\u7528 '(' \u6216 ')'\u3002
\n(?:pattern) \u5339\u914d pattern \u4f46\u4e0d\u83b7\u53d6\u5339\u914d\u7ed3\u679c\uff0c\u4e5f\u5c31\u662f\u8bf4\u8fd9\u662f\u4e00\u4e2a\u975e\u83b7\u53d6\u5339\u914d\uff0c\u4e0d\u8fdb\u884c\u5b58\u50a8\u4f9b\u4ee5\u540e\u4f7f\u7528\u3002\u8fd9\u5728\u4f7f\u7528 "\u6216" \u5b57\u7b26 (\u2502) \u6765\u7ec4\u5408\u4e00\u4e2a\u6a21\u5f0f\u7684\u5404\u4e2a\u90e8\u5206\u662f\u5f88\u6709\u7528\u3002\u4f8b\u5982\uff0c 'industr(?:y\u2502ies) \u5c31\u662f\u4e00\u4e2a\u6bd4 'industry\u2502industries' \u66f4\u7b80\u7565\u7684\u8868\u8fbe\u5f0f\u3002
\n(?=pattern) \u6b63\u5411\u9884\u67e5\uff0c\u5728\u4efb\u4f55\u5339\u914d pattern \u7684\u5b57\u7b26\u4e32\u5f00\u59cb\u5904\u5339\u914d\u67e5\u627e\u5b57\u7b26\u4e32\u3002\u8fd9\u662f\u4e00\u4e2a\u975e\u83b7\u53d6\u5339\u914d\uff0c\u4e5f\u5c31\u662f\u8bf4\uff0c\u8be5\u5339\u914d\u4e0d\u9700\u8981\u83b7\u53d6\u4f9b\u4ee5\u540e\u4f7f\u7528\u3002\u4f8b\u5982\uff0c 'Windows (?=95\u250298\u2502NT\u25022000)' \u80fd\u5339\u914d "Windows 2000" \u4e2d\u7684 "Windows" \uff0c\u4f46\u4e0d\u80fd\u5339\u914d "Windows 3.1" \u4e2d\u7684 "Windows"\u3002\u9884\u67e5\u4e0d\u6d88\u8017\u5b57\u7b26\uff0c\u4e5f\u5c31\u662f\u8bf4\uff0c\u5728\u4e00\u4e2a\u5339\u914d\u53d1\u751f\u540e\uff0c\u5728\u6700\u540e\u4e00\u6b21\u5339\u914d\u4e4b\u540e\u7acb\u5373\u5f00\u59cb\u4e0b\u4e00\u6b21\u5339\u914d\u7684\u641c\u7d22\uff0c\u800c\u4e0d\u662f\u4ece\u5305\u542b\u9884\u67e5\u7684\u5b57\u7b26\u4e4b\u540e\u5f00\u59cb\u3002
\n(?!pattern) \u8d1f\u5411\u9884\u67e5\uff0c\u5728\u4efb\u4f55\u4e0d\u5339\u914dNegative lookahead matches the search string at any point where a string not matching pattern \u7684\u5b57\u7b26\u4e32\u5f00\u59cb\u5904\u5339\u914d\u67e5\u627e\u5b57\u7b26\u4e32\u3002\u8fd9\u662f\u4e00\u4e2a\u975e\u83b7\u53d6\u5339\u914d\uff0c\u4e5f\u5c31\u662f\u8bf4\uff0c\u8be5\u5339\u914d\u4e0d\u9700\u8981\u83b7\u53d6\u4f9b\u4ee5\u540e\u4f7f\u7528\u3002\u4f8b\u5982'Windows (?!95\u250298\u2502NT\u25022000)' \u80fd\u5339\u914d "Windows 3.1" \u4e2d\u7684 "Windows"\uff0c\u4f46\u4e0d\u80fd\u5339\u914d "Windows 2000" \u4e2d\u7684 "Windows"\u3002\u9884\u67e5\u4e0d\u6d88\u8017\u5b57\u7b26\uff0c\u4e5f\u5c31\u662f\u8bf4\uff0c\u5728\u4e00\u4e2a\u5339\u914d\u53d1\u751f\u540e\uff0c\u5728\u6700\u540e\u4e00\u6b21\u5339\u914d\u4e4b\u540e\u7acb\u5373\u5f00\u59cb\u4e0b\u4e00\u6b21\u5339\u914d\u7684\u641c\u7d22\uff0c\u800c\u4e0d\u662f\u4ece\u5305\u542b\u9884\u67e5\u7684\u5b57\u7b26\u4e4b\u540e\u5f00\u59cb
\nx\u2502y \u5339\u914d x \u6216 y\u3002\u4f8b\u5982\uff0c'z\u2502food' \u80fd\u5339\u914d "z" \u6216 "food"\u3002'(z\u2502f)ood' \u5219\u5339\u914d "zood" \u6216 "food"\u3002
\n[xyz] \u5b57\u7b26\u96c6\u5408\u3002\u5339\u914d\u6240\u5305\u542b\u7684\u4efb\u610f\u4e00\u4e2a\u5b57\u7b26\u3002\u4f8b\u5982\uff0c '[abc]' \u53ef\u4ee5\u5339\u914d "plain" \u4e2d\u7684 'a'\u3002
\n[^xyz] \u8d1f\u503c\u5b57\u7b26\u96c6\u5408\u3002\u5339\u914d\u672a\u5305\u542b\u7684\u4efb\u610f\u5b57\u7b26\u3002\u4f8b\u5982\uff0c '[^abc]' \u53ef\u4ee5\u5339\u914d "plain" \u4e2d\u7684'p'\u3002
\n[a-z] \u5b57\u7b26\u8303\u56f4\u3002\u5339\u914d\u6307\u5b9a\u8303\u56f4\u5185\u7684\u4efb\u610f\u5b57\u7b26\u3002\u4f8b\u5982\uff0c'[a-z]' \u53ef\u4ee5\u5339\u914d 'a' \u5230 'z' \u8303\u56f4\u5185\u7684\u4efb\u610f\u5c0f\u5199\u5b57\u6bcd\u5b57\u7b26\u3002
\n[^a-z] \u8d1f\u503c\u5b57\u7b26\u8303\u56f4\u3002\u5339\u914d\u4efb\u4f55\u4e0d\u5728\u6307\u5b9a\u8303\u56f4\u5185\u7684\u4efb\u610f\u5b57\u7b26\u3002\u4f8b\u5982\uff0c'[^a-z]' \u53ef\u4ee5\u5339\u914d\u4efb\u4f55\u4e0d\u5728 'a' \u5230 'z' \u8303\u56f4\u5185\u7684\u4efb\u610f\u5b57\u7b26\u3002
\n\b \u5339\u914d\u4e00\u4e2a\u5355\u8bcd\u8fb9\u754c\uff0c\u4e5f\u5c31\u662f\u6307\u5355\u8bcd\u548c\u7a7a\u683c\u95f4\u7684\u4f4d\u7f6e\u3002\u4f8b\u5982\uff0c 'er\b' \u53ef\u4ee5\u5339\u914d"never" \u4e2d\u7684 'er'\uff0c\u4f46\u4e0d\u80fd\u5339\u914d "verb" \u4e2d\u7684 'er'\u3002
\nB \u5339\u914d\u975e\u5355\u8bcd\u8fb9\u754c\u3002'erB' \u80fd\u5339\u914d "verb" \u4e2d\u7684 'er'\uff0c\u4f46\u4e0d\u80fd\u5339\u914d "never" \u4e2d\u7684 'er'\u3002
\ncx \u5339\u914d\u7531x\u6307\u660e\u7684\u63a7\u5236\u5b57\u7b26\u3002\u4f8b\u5982\uff0c cM \u5339\u914d\u4e00\u4e2a Control-M \u6216\u56de\u8f66\u7b26\u3002 x \u7684\u503c\u5fc5\u987b\u4e3a A-Z \u6216 a-z \u4e4b\u4e00\u3002\u5426\u5219\uff0c\u5c06 c \u89c6\u4e3a\u4e00\u4e2a\u539f\u4e49\u7684 'c' \u5b57\u7b26\u3002
\nd \u5339\u914d\u4e00\u4e2a\u6570\u5b57\u5b57\u7b26\u3002\u7b49\u4ef7\u4e8e [0-9]\u3002
\nD \u5339\u914d\u4e00\u4e2a\u975e\u6570\u5b57\u5b57\u7b26\u3002\u7b49\u4ef7\u4e8e [^0-9]\u3002
\nf \u5339\u914d\u4e00\u4e2a\u6362\u9875\u7b26\u3002\u7b49\u4ef7\u4e8e x0c \u548c cL\u3002
\n\u5339\u914d\u4e00\u4e2a\u6362\u884c\u7b26\u3002\u7b49\u4ef7\u4e8e x0a \u548c cJ\u3002
\n\u5339\u914d\u4e00\u4e2a\u56de\u8f66\u7b26\u3002\u7b49\u4ef7\u4e8e x0d \u548c cM\u3002
\ns \u5339\u914d\u4efb\u4f55\u7a7a\u767d\u5b57\u7b26\uff0c\u5305\u62ec\u7a7a\u683c\u3001\u5236\u8868\u7b26\u3001\u6362\u9875\u7b26\u7b49\u7b49\u3002\u7b49\u4ef7\u4e8e [ f v]\u3002
\nS \u5339\u914d\u4efb\u4f55\u975e\u7a7a\u767d\u5b57\u7b26\u3002\u7b49\u4ef7\u4e8e [^ f v]\u3002
\n\u5339\u914d\u4e00\u4e2a\u5236\u8868\u7b26\u3002\u7b49\u4ef7\u4e8e x09 \u548c cI\u3002
\nv \u5339\u914d\u4e00\u4e2a\u5782\u76f4\u5236\u8868\u7b26\u3002\u7b49\u4ef7\u4e8e x0b \u548c cK\u3002
\nw \u5339\u914d\u5305\u62ec\u4e0b\u5212\u7ebf\u7684\u4efb\u4f55\u5355\u8bcd\u5b57\u7b26\u3002\u7b49\u4ef7\u4e8e'[A-Za-z0-9_]'\u3002
\nW \u5339\u914d\u4efb\u4f55\u975e\u5355\u8bcd\u5b57\u7b26\u3002\u7b49\u4ef7\u4e8e '[^A-Za-z0-9_]'\u3002
\nxn \u5339\u914d n\uff0c\u5176\u4e2d n \u4e3a\u5341\u516d\u8fdb\u5236\u8f6c\u4e49\u503c\u3002\u5341\u516d\u8fdb\u5236\u8f6c\u4e49\u503c\u5fc5\u987b\u4e3a\u786e\u5b9a\u7684\u4e24\u4e2a\u6570\u5b57\u957f\u3002\u4f8b\u5982\uff0c 'x41' \u5339\u914d "A"\u3002'x041' \u5219\u7b49\u4ef7\u4e8e 'x04' & "1"\u3002\u6b63\u5219\u8868\u8fbe\u5f0f\u4e2d\u53ef\u4ee5\u4f7f\u7528 ASCII \u7f16\u7801\u3002.
\num \u5339\u914d num\uff0c\u5176\u4e2d num \u662f\u4e00\u4e2a\u6b63\u6574\u6570\u3002\u5bf9\u6240\u83b7\u53d6\u7684\u5339\u914d\u7684\u5f15\u7528\u3002\u4f8b\u5982\uff0c'(.)' \u5339\u914d\u4e24\u4e2a\u8fde\u7eed\u7684\u76f8\u540c\u5b57\u7b26\u3002
\n\u6807\u8bc6\u4e00\u4e2a\u516b\u8fdb\u5236\u8f6c\u4e49\u503c\u6216\u4e00\u4e2a\u540e\u5411\u5f15\u7528\u3002\u5982\u679c \u4e4b\u524d\u81f3\u5c11 n \u4e2a\u83b7\u53d6\u7684\u5b50\u8868\u8fbe\u5f0f\uff0c\u5219 n \u4e3a\u540e\u5411\u5f15\u7528\u3002\u5426\u5219\uff0c\u5982\u679c n \u4e3a\u516b\u8fdb\u5236\u6570\u5b57 (0-7)\uff0c\u5219 n \u4e3a\u4e00\u4e2a\u516b\u8fdb\u5236\u8f6c\u4e49\u503c\u3002
\nm \u6807\u8bc6\u4e00\u4e2a\u516b\u8fdb\u5236\u8f6c\u4e49\u503c\u6216\u4e00\u4e2a\u540e\u5411\u5f15\u8c29\uff28\u7efb? m \u4e4b\u524d\u81f3\u5c11\u6709is preceded by at least nm \u4e2a\u83b7\u53d6\u5f97\u5b50\u8868\u8fbe\u5f0f\uff0c\u5219 nm \u4e3a\u540e\u5411\u5f15\u7528\u3002\u5982\u679c m \u4e4b\u524d\u81f3\u5c11\u6709 n \u4e2a\u83b7\u53d6\uff0c\u5219 n \u4e3a\u4e00\u4e2a\u540e\u8ddf\u6587\u5b57 m \u7684\u540e\u5411\u5f15\u7528\u3002\u5982\u679c\u524d\u9762\u7684\u6761\u4ef6\u90fd\u4e0d\u6ee1\u8db3\uff0c\u82e5 n \u548c m \u5747\u4e3a\u516b\u8fdb\u5236\u6570\u5b57 (0-7)\uff0c\u5219 m \u5c06\u5339\u914d\u516b\u8fdb\u5236\u8f6c\u4e49\u503c nm\u3002
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