KMP 算法实现

using System;
using System.Collections.Generic;
using System.Linq;
namespace KMP
{
    class Program
    {
        static void Main(string[] args)
        {
            string s = "ABCDAABEFAECA";
            string comp = "AECA";
            sss(s, comp);
            Console.Read();
        }

        private static void sss(string s, string comp)
        {
            int j = 0;
            for (int i = 0; i < s.Length;)
            {
                if (s[i] != comp[j])
                {
                    //i--;
                    //判断需要跳过几个
                    int temp = j - Pd(j, comp);
                    if (temp==1)
                    {
                        i--;
                    }
                    if (temp==0)
                    {
                        i++;
                    }
                    j = 0;
                    i += temp;
                }
                else
                {
                    j++;
                    i++;
                    if (j == comp.Length)
                    {
                        Console.WriteLine("找到了匹配的字符串,---->位置在:{0}", i - j );
                        return;
                    }
                }
            }
            Console.WriteLine("没有找到哦");
            //匹配成功的表现是什么?

        }
        /// <summary>
        /// 移动位数=已匹配的字符数-对应的部分匹配值
        /// </summary>
        private static int Pd(int j, string comp)
        {
            comp = comp.Substring(0, j);
            //要得到前缀和,后缀
            int bf1 = bf(qian(comp), hou(comp));
            return bf1;
        }
        public static string[] qian(string comp)
        {
            List<string> tStr = new List<string>();
            string s = string.Empty;
            for (int i = 0; i < comp.Length - 1; i++)
            {
                s += comp[i];
                tStr.Add(s);
            }
            return tStr.ToArray();
        }
        public static string[] hou(string comp)
        {
            List<string> tStr = new List<string>();
            string s = string.Empty;
            for (int i = comp.Length - 1; i > 0; i--)
            {
                s = comp.Substring(1, i);
                tStr.Add(s);
            }
            return tStr.ToArray();
        }
        /// <summary>
        /// 对应部分匹配值
        /// </summary>
        /// <param name="f"></param>
        /// <param name="b"></param>
        /// <returns></returns>
        public static int bf(string[] f, string[] b)
        {
            //查看重复的次数
            int j = 0;
            for (int i = 0; i < f.Length; i++)
            {
                if (f.Contains(b[i]))
                {
                    j++;
                }
            }
            return j;
        }
    }
}