kmp算法

kmp算法

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
/*
kmp
*/
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<string>
using namespace std;
int nxt[1003],len1,len2;
char s1[1000003],s2[1003];
void initNxt()
{
	nxt[0]=-1;
	int j=-1;
	for(int i=1;i<=len2-1;++i)
	{
		while(j!=-1&&s2[i]!=s2[j+1])
			j=nxt[j];
		if(s2[i]==s2[j+1])++j;
			nxt[i]=j;
	}
}
void findApr()
{
	int i,j;
	for(i=0,j=-1;i<=len1-1;++i)
	{
		while(j!=-1&&s1[i]!=s2[j+1])
			j=nxt[j];
		if(s1[i]==s2[j+1])++j;//find the same
		if(j==len2-1)
		{
			printf("%d\n",i-j+1);
		}
	}
}
int main()
{
	freopen("kmp.in","r",stdin);
	//freopen("kmp.out","w",stdout);
	scanf("%s %s",s1,s2);
	len1=strlen(s1),len2=strlen(s2);
	initNxt();
	findApr();
	for(int i=0;i<=len2-1;++i)
	{
		printf("%d ",nxt[i]+1);
	}
	printf("\n");
	return 0;
}
0%