//KMP匹配串的位置
public int Index(StringLink s, int where = 1)
{
if (s.IsEmpty() || this.IsEmpty() || where < 1 || where > this.GetLength())
{
Console.WriteLine("串不能为空或索引非法！");
return(0);
}
int[] nextval = this._GetNextVal(s);
int matchLength = s.GetLength();
int length = this.GetLength();
int i = where;
int j = 1;
while (i <= length && j <= matchLength)
{
if (j == 0 || this[i] == s[j])
{
j++;
i++;
}
else
{
j = nextval[j];
}
}
if (j > matchLength)
{
return(i - matchLength);
}
return(0);
}
private int[] _GetNextVal(StringLink s)
{
int length = s.GetLength();
int[] nextval = new int[length + 1];
int i = 1;
int j = 0;
nextval[1] = 0;
for (; i < length;)
{
if (j == 0 || s[i] == s[j])
{
i++;
j++;
if (s[i] == s[j])
{
nextval[i] = nextval[j];
}
else
{
nextval[i] = j;
}
}
else
{
j = nextval[j];
}
}
return(nextval);
}
//替换字符串
public int Replace(StringLink match, StringLink replace, int index = 1)
{
if (match.IsEmpty() || this.IsEmpty())
{
Console.WriteLine("当前串或匹配串不能为空！");
return(0);
}
if (index < 1 || index > this.GetLength())
{
Console.WriteLine("索引错误！");
return(0);
}
int matchIndex = this.Index(match, index);
if (matchIndex != 0)
{
this.Delete(matchIndex, match.GetLength());
if (matchIndex - 1 == this.GetLength())
{
this.Concat(replace);
}
else
{
this.Insert(matchIndex, replace);
}
return(1);
}
return(0);
}
static void PrintStringLink(StringLink s, string text = "输出:")
{
Console.Write(text);
for (int i = 0; i < s.GetLength(); i++)
{
Console.Write(s[i + 1]);
}
Console.WriteLine();
}
