KMP算法代码（c#）

呵呵  大家可以把matchCount 替换成next  我是为了讲解方便 写成matchCount 呵呵

 

public static List<int> Match(string content, string pattern) //返回匹配的位置
        {
            int[] matchCount = Next(pattern);

            List<int> matchPosition = new List<int>();

            int j=-1;

            for (int i = 0; i < content.Length; i++)
            {
                while ( (content[i] != pattern[j + 1])&&(j>0)) j = matchCount[j];

                if(content[i]==pattern[j+1]) j=j+1;


                if (j == pattern.Length-1)
                {
                    matchPosition.Add(i-pattern.Length+1);

                    j = matchCount[j];
                }

            }

            return matchPosition;
        }


        public static int[] Next(string s)
        {
            int[] matchCount = new int[s.Length];

            int j = 0;
           
            matchCount[1] = 0;

            for (int i = 2; i < s.Length; i++)
            {
                while ((s[i] != s[j+1])&&(j>0)) j = matchCount[j];

                if (s[i] == s[j + 1]) j = j + 1;

                matchCount[i] = j;                
            }

            return matchCount;
        }
    }