{"id":1743,"date":"2017-02-04T18:14:46","date_gmt":"2017-02-04T10:14:46","guid":{"rendered":"http:\/\/cn.hostease.com\/xueyuan\/?p=1743"},"modified":"2025-01-12T20:04:21","modified_gmt":"2025-01-12T12:04:21","slug":"%e7%bb%8f%e5%85%b8%e7%ae%97%e6%b3%95%e9%a2%98%e6%af%8f%e6%97%a5%e6%bc%94%e7%bb%83-%e7%ac%ac%e4%b8%83%e9%a2%98-kmp%e7%ae%97%e6%b3%95","status":"publish","type":"post","link":"https:\/\/cn.hostease.com\/xueyuan\/jishu\/%e7%bb%8f%e5%85%b8%e7%ae%97%e6%b3%95%e9%a2%98%e6%af%8f%e6%97%a5%e6%bc%94%e7%bb%83-%e7%ac%ac%e4%b8%83%e9%a2%98-kmp%e7%ae%97%e6%b3%95\/","title":{"rendered":"\u7ecf\u5178\u7b97\u6cd5\u9898\u6bcf\u65e5\u6f14\u7ec3\u2014\u2014\u7b2c\u4e03\u9898 KMP\u7b97\u6cd5"},"content":{"rendered":"\n

\u5728\u5927\u5b66\u7684\u65f6\u5019\uff0c\u5e94\u8be5\u5728\u6570\u636e\u7ed3\u6784\u91cc\u9762\u90fd\u770b\u8fc7kmp\u7b97\u6cd5\u5427\uff0c\u4e0d\u77e5\u9053\u6709\u591a\u5c11\u8001\u5e08\u5bf9\u8be5\u7b97\u6cd5\u662f\u4e00\u7b14\u5e26\u8fc7\u7684\uff0c\u81f3\u5c11\u6211\u4eec\u4ee5\u524d\u662f\u7684\uff0c<\/p>\n\n\n\n

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 <\/p>\n\n\n\n

\u4e8c\uff1aKMP\u7b97\u6cd5<\/p>\n\n\n\n

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\"\"<\/a><\/figure>\n\n\n\n

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-1        \u5f53j=0\u65f6<\/p>\n\n\n\n

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next[j]=k\uff0c\u6211\u4eec\u6765\u6c42next[j+1]=\uff1f\u7684\u95ee\u9898\uff1f\u5176\u5b9e\u4e5f\u5c31\u662f\u4e24\u79cd\u60c5\u51b5\uff1a<\/p>\n\n\n\n

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\n
<\/span><\/div>\n
 1 using System;\n 2 using System.Collections.Generic;\n 3 using System.Linq;\n 4 using System.Text;\n 5 \n 6 namespace SupportCenter.Test\n 7 {\n 8     public class Program\n 9     {\n10         static void Main(string[] args)\n11         {\n12             string zstr = \"ababcabababdc\";\n13 \n14             string mstr = \"babdc\";\n15 \n16             var index = KMP(zstr, mstr);\n17 \n18             if (index == -1)\n19                 Console.WriteLine(\"\u6ca1\u6709\u5339\u914d\u7684\u5b57\u7b26\u4e32\uff01\");\n20             else\n21                 Console.WriteLine(\"\u54c8\u54c8\uff0c\u627e\u5230\u5b57\u7b26\u5566\uff0c\u4f4d\u7f6e\u4e3a\uff1a\" + index);\n22 \n23             Console.Read();\n24         }\n25 \n26         static int KMP(string bigstr, string smallstr)\n27         {\n28             int i = 0;\n29             int j = 0;\n30 \n31             \/\/\u8ba1\u7b97\u201c\u524d\u7f00\u4e32\u201d\u548c\u201c\u540e\u7f00\u4e32\u201c\u7684next\n32             int[] next = GetNextVal(smallstr);\n33 \n34             while (i < bigstr.Length && j < smallstr.Length)\n35             {\n36                 if (j == -1 || bigstr[i] == smallstr[j])\n37                 {\n38                     i++;\n39                     j++;\n40                 }\n41                 else\n42                 {\n43                     j = next[j];\n44                 }\n45             }\n46 \n47             if (j == smallstr.Length)\n48                 return i - smallstr.Length;\n49 \n50             return -1;\n51         }\n52 \n53         \/\/\/ <summary>\n54         \/\/\/ p0,p1....pk-1         \uff08\u524d\u7f00\u4e32\uff09\n55         \/\/\/ pj-k,pj-k+1....pj-1   \uff08\u540e\u7f00\u4e32)\n56         \/\/\/ <\/summary>\n57         \/\/\/ <param name=\"match\"><\/param>\n58         \/\/\/ <returns><\/returns>\n59         static int[] GetNextVal(string smallstr)\n60         {\n61             \/\/\u524d\u7f00\u4e32\u8d77\u59cb\u4f4d\u7f6e(\"-1\"\u662f\u65b9\u4fbf\u8ba1\u7b97\uff09\n62             int k = -1;\n63 \n64             \/\/\u540e\u7f00\u4e32\u8d77\u59cb\u4f4d\u7f6e\uff08\"-1\"\u662f\u65b9\u4fbf\u8ba1\u7b97\uff09\n65             int j = 0;\n66 \n67             int[] next = new int[smallstr.Length];\n68 \n69             \/\/\u6839\u636e\u516c\u5f0f\uff1a j=0\u65f6\uff0cnext[j]=-1\n70             next[j] = -1;\n71 \n72             while (j < smallstr.Length - 1)\n73             {\n74                 if (k == -1 || smallstr[k] == smallstr[j])\n75                 {\n76                     \/\/pk=pj\u7684\u60c5\u51b5: next[j+1]=k+1 => next[j+1]=next[j]+1\n77                     next[++j] = ++k;\n78                 }\n79                 else\n80                 {\n81                     \/\/pk != pj \u7684\u60c5\u51b5:\u6211\u4eec\u9012\u63a8 k=next[k];\n82                     \/\/\u8981\u4e48\u627e\u5230\uff0c\u8981\u4e48k=-1\u4e2d\u6b62\n83                     k = next[k];\n84                 }\n85             }\n86 \n87             return next;\n88         }\n89     }\n90 }\n\n\n\n\n\u6587\u7ae0\u6765\u81ea\u7f51\u7edc\u535a\u5ba2\u3002\u539f\u6587\u5730\u5740\uff1ahttps:\/\/www.cnblogs.com\/huangxincheng\/archive\/2012\/12\/01\/2796993.html<\/pre>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
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