kmp

kmp看不懂啊!先放着再说!

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#include<stdio.h>
#include<string.h>
int next[10001];
void make_next(char sstr[],int ls)
{
	next[0]=-1;
	int j=0;int k=-1;
	while(j<ls-1)
	{
		if(k==-1||sstr[j]==sstr[k])
		{j++;k++;next[j]=k;}
		else
			k=next[k];
	}
}
int find_substr(char mstr[],int lm,char sstr[],int ls)
{
	int rst=-1;
	make_next(sstr,ls);
	int i,j,n;i=j=n=0;
	while(i<lm)
	{
		n++;
		if(mstr[i]==sstr[j]||j==-1)
		{i++;j++;}
		else j=next[j];
		if(j==ls)
		{rst=i-ls;break;}
	}
	return rst;
}
int main()
{
	char mstr[20];char sstr[4];
	scanf("%s%s",mstr,sstr);
	printf("位置在%d!\n",find_substr(mstr,strlen(mstr),sstr,strlen(sstr)));
	return 1;
}