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#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
using namespace std;
#define sigma 26
#define N 1000010
int l1[N],l2[N];
struct Palindromic_Tree{
    int next[N][sigma],fail[N],ch[N];
    int cnt[N],kind[N],len[N];
    int last,int_tot,char_tot;
    void init(){
        int_tot+=2;
        len[int_tot-1]=-1;
        ch[char_tot]=-1;
        fail[0]=1;
    }
    int get_fail(int x){
        while(ch[char_tot-len[x]-1]!=ch[char_tot])x=fail[x];
        return x;
    }
    void insert(int c){
        ch[++char_tot]=c-'a';
        int cur=get_fail(last);
        //cout<<cur<<endl;
        if(!next[cur][c-'a']){
            int now=int_tot++;
            len[now]=len[cur]+2;
            fail[now]=next[get_fail(fail[cur])][c-'a'];
            next[cur][c-'a']=now;
            kind[now]=kind[fail[now]]+1;
        }
        last=next[cur][c-'a'];
        cnt[last]++;
    }
    void count(){
        for(int i=int_tot-1;i>-1;i--)cnt[fail[i]]+=cnt[i];
    }
    int build(string s){
        init();
        int le=s.size();
        for(int i=0;i<le;i++){
            insert(s[i]);
        }
        return le;
    }
    int build(char *s){
        init();
        int le=strlen(s);
        for(int i=0;i<le;i++){
            insert(s[i]);
        }
        return le;
    }
}tree;
int main(){
}