KMP板子（题）

\(P3375 【模板】KMP\)

https://www.luogu.com.cn/problem/P3375

include<bits/stdc++.h>

using namespace std;
const int N=1e7+5;
vector get_pi(string s){
int n=s.length();
vector pi(n);
for(int i=1;i<n;++i){
int j=pi[i-1];
while(j&&s[i]-s[j])j=pi[j-1];
if(s[i]s[j])j++;
pi[i]=j;
}
return pi;
}
string s,sl;
vector get_id(string text,string pattern){
string cur=pattern+'#'+text;
int lent=text.size(),lens=pattern.size();
vector v;
vector lps=get_pi(cur);
for(int i=lens+1;i<=lent+lens;++i){
if(lps[i]lens)v.push_back(i-2*lens);
}
return v;
}
int main(){
cin>>s>>sl;
vector id=get_id(s,sl);
for(int i=0;i<(int)id.size();++i)printf("%d\n",id[i]+1);
vector st=get_pi(sl);
for(int i=0;i<st.size();++i)printf("%d ",st[i]);
return 0;
}

\(Seek the Name, Seek the Fame\)

include<bits/stdc++.h>

using namespace std;
const int N=4e5+5;
int ans[N],nt[N],len;
char s[N];
void get_pi(){
int i=0,j=-1;
nt[0]=-1;
while(i<len){
if(j-1||s[i]s[j])nt[++i]=++j;
else j=nt[j];
}
}
int main(){
while(scanf("%s",s)!=EOF){
int t=0;
len=strlen(s);
memset(nt,0,sizeof nt);
get_pi();
for(int i=len;i>0;i=nt[i])ans[++t]=nt[i];
for(int i=t-1;i>0;i--)printf("%d ",ans[i]);
printf("%d \n",len);
}
return 0;
}

看数据范围……
也是数组开小了，\(WA\)了一发