HDU 2087 kmp模板题

时间:2024-10-08 17:36:44

s为主串 t为模板串 求t的nextt 加const

#include<stdio.h>
#include<string.h>
#include<algorithm>
#include<map>
#include<math.h>
#include<queue>
using namespace std;
char s[1005];
char t[1005];
int nextt[1005];
void makenext(const char t[])
{
int i=0,j=-1;
int len=strlen(t);
nextt[0]=-1;
while(i<len)
{
if(j==-1||t[i]==t[j])
{
i++;
j++;
       nextt[i]=j;
}
else j=nextt[j];
}
}
int ans;
void kmp(const char s[],const char t[])
{
makenext(t);
int len1=strlen(s);
int len2=strlen(t);
int i=0,j=0;
while(i<len1)
{
if(j==-1||s[i]==t[j])
{
i++;
j++;
}
else j=nextt[j];
if(j==len2)
{
ans++;
j=0;
}
}
}
int main(){
while(~scanf("%s",s))
{
if(strcmp(s,"#")==0)
break;
scanf("%s",t);
ans=0;
kmp(s,t);
printf("%d\n",ans);
}
}