#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(long long i=0;i<(long long)(n);i++)
#define REP(i,k,n) for(long long i=k;i<(long long)(n);i++)
#define all(a) a.begin(),a.end()
#define pb emplace_back
#define eb emplace_back
#define lb(v,k) (lower_bound(all(v),k)-v.begin())
#define ub(v,k) (upper_bound(all(v),k)-v.begin())
#define fi first
#define se second
#define pi M_PI
#define PQ(T) priority_queue<T>
#define SPQ(T) priority_queue<T,vector<T>,greater<T>>
#define dame(a) {out(a);return 0;}
#define decimal cout<<fixed<<setprecision(15);
#define dupli(a) {sort(all(a));a.erase(unique(all(a)),a.end());}
typedef long long ll;
typedef pair<ll,ll> P;
typedef tuple<ll,ll,ll> PP;
typedef tuple<ll,ll,ll,ll> PPP;
typedef multiset<ll> S;
using vi=vector<ll>;
using vvi=vector<vi>;
using vvvi=vector<vvi>;
using vvvvi=vector<vvvi>;
using vp=vector<P>;
using vvp=vector<vp>;
using vb=vector<bool>;
using vvb=vector<vb>;
const ll inf=1001001001001001001;
const ll INF=1001001001;
const ll mod=1000000007;
const double eps=1e-10;
template<class T> bool chmin(T&a,T b){if(a>b){a=b;return true;}return false;}
template<class T> bool chmax(T&a,T b){if(a<b){a=b;return true;}return false;}
template<class T> void out(T a){cout<<a<<'\n';}
template<class T> void outp(T a){cout<<'('<<a.fi<<','<<a.se<<')'<<'\n';}
template<class T> void outvp(T v){rep(i,v.size())cout<<'('<<v[i].fi<<','<<v[i].se<<')';cout<<'\n';}
template<class T> void outvvp(T v){rep(i,v.size())outvp(v[i]);}
template<class T> void outv(T v){rep(i,v.size()){if(i)cout<<' ';cout<<v[i];}cout<<'\n';}
template<class T> void outvv(T v){rep(i,v.size())outv(v[i]);}
template<class T> bool isin(T x,T l,T r){return (l)<=(x)&&(x)<=(r);}
template<class T> void yesno(T b){if(b)out("yes");else out("no");}
template<class T> void YesNo(T b){if(b)out("Yes");else out("No");}
template<class T> void YESNO(T b){if(b)out("YES");else out("NO");}
template<class T> void noyes(T b){if(b)out("no");else out("yes");}
template<class T> void NoYes(T b){if(b)out("No");else out("Yes");}
template<class T> void NOYES(T b){if(b)out("NO");else out("YES");}
void outs(ll a,ll b){if(a>=inf-100)out(b);else out(a);}
ll gcd(ll a,ll b){if(b==0)return a;return gcd(b,a%b);}
ll modpow(ll a,ll b){ll res=1;a%=mod;while(b){if(b&1)res=res*a%mod;a=a*a%mod;b>>=1;}return res;}
vi manacher(string &s){
int i=0,j=0;
vi res(s.size());
while(i<s.size()){
while(i-j>=0&&i+j<s.size()&&s[i-j]==s[i+j])j++;
res[i]=j;
int k=1;
while(i-k>=0&&k+res[i-k]<j){
res[i+k]=res[i-k];
k++;
}
i+=k;j-=k;
}
return res;
}
vi SA_IS(vi str, int var) {
if(str.size() == 1) {
vi ret(1,0);
return ret;
}
str.push_back(0);
int si = str.size();
vi st(var, 0), en(var, 0);
vi SL(si, 0); //s..0, l..1
vi SA(si, -1);
vi LMS;
vi is_LMS(si, -1);
rep(i,str.size()) en[str[i]]++;
for(int i = 1; i < var; i++) en[i] += en[i-1];
for(int i = 1; i < var; i++) st[i] = en[i-1];
SL[str.size()-1] = 0;
for(int i = str.size()-2; i >= 0; i--) {
if(str[i] == str[i+1]) {
SL[i] = SL[i+1];
continue;
}
if(str[i] > str[i+1]) SL[i] = 1;
else SL[i] = 0;
}
for(int i = 1; i < str.size(); i++) {
if(SL[i] == 0 && SL[i-1] == 1) {
SA[--en[str[i]]] = i;
LMS.push_back(i);
is_LMS[i] = 1;
}
}
rep(i,var-1) en[i] = st[i+1];
en[var-1] = str.size();
rep(i,str.size()) if(SA[i] > 0 && SL[SA[i]-1] == 1) { SA[st[str[SA[i]-1]]++] = SA[i]-1; }
st[0] = 0;
for(int i = 1; i < var; i++) st[i] = en[i-1];
for(int i = 1; i < str.size(); i++) if(SA[i] != -1 && SL[SA[i]] == 0) { SA[i] = -1; }
for(int i = str.size()-1; i >= 1; i--) if(SA[i] > 0 && SL[SA[i]-1] == 0) { SA[--en[str[SA[i]-1]]] = SA[i]-1; }
rep(i,var-1) en[i] = st[i+1];
en[var-1] = str.size();
int counter = 0;
vi pre_sa, new_sa;
rep(i,SA.size()) if(is_LMS[SA[i]] != -1) {
is_LMS[SA[i]] = ++counter;
new_sa.clear();
for(int j = SA[i]; j < SA.size(); j++) {
new_sa.push_back(str[j]);
if(j != SA[i] && is_LMS[j] != -1) {
break;
}
}
if(pre_sa == new_sa) {
is_LMS[SA[i]] = --counter;
}
pre_sa = new_sa;
}
vi new_str;
vi rev((int)LMS.size()+1, 0);
counter = 0;
rep(i,is_LMS.size()) {
if(is_LMS[i] != -1) {
new_str.push_back(is_LMS[i]);
rev[counter++] = i;
}
}
vi rec = SA_IS(new_str, new_str.size()+1);
rep(i,SA.size()) SA[i] = -1;
for(int i = rec.size()-1; i >= 0; i--) { SA[--en[str[rev[rec[i]]]]] = rev[rec[i]]; }
rep(i,var-1) en[i] = st[i+1];
en[var-1] = str.size();
rep(i,str.size()) if(SA[i] > 0 && SL[SA[i]-1] == 1) { SA[st[str[SA[i]-1]]++] = SA[i]-1; }
for(int i = 1; i < str.size(); i++) if(SA[i] != -1 && SL[SA[i]] == 0) { SA[i] = -1; }
for(int i = str.size()-1; i >= 1; i--) if(SA[i] > 0 && SL[SA[i]-1] == 0) { SA[--en[str[SA[i]-1]]] = SA[i]-1; }
SA.erase(SA.begin());
return SA;
}
typedef unsigned long long ull;
typedef vector<ull> vu;
int main(){
string s;cin>>s;
string t;
rep(i,s.size()){
if(i)t+='x';
t+=s[i];
}
vi m=manacher(t);
vp q;
rep(i,m.size()){
if(i&1)q.pb(i/2-m[i]/2+1,i/2+m[i]/2);
else q.pb(i/2-(m[i]-1)/2,i/2+(m[i]-1)/2);
}
ll n=s.size();
vu has(n+1);
rep(i,n)has[i+1]=(has[i]*37+(s[i]-'a'+1));
vi str(n);
rep(i,n)str[i]=s[i]-'a'+1;
vi sa=SA_IS(str,30);
sa.insert(sa.begin(),n);
vi rs(n+1);
rep(i,n+1)rs[sa[i]]=i;
ll ans=0;
vu mp(n+5);
mp[0]=1;
rep(i,n+4)mp[i+1]=mp[i]*37;
// outvp(q);outv(sa);outv(rs);outv(has);
for(auto x:q){
ll len=x.se-x.fi+1;
ll to=rs[x.fi],ng=n+1;
while(ng-to>1){
ll md=(to+ng)/2;
ll id=sa[md];
if(id+len>n){ng=md;continue;}
ull a=(has[x.se+1]-has[x.fi]*mp[len]);
ull b=(has[id+len]-has[id]*mp[len]);
if(a==b)to=md;
else ng=md;
}
ll fr=rs[x.fi],ngg=0;
while(fr-ngg>1){
ll md=(fr+ngg)/2;
ll id=sa[md];
if(id+len>n){ngg=md;continue;}
ull a=(has[x.se+1]-has[x.fi]*mp[len]);
ull b=(has[id+len]-has[id]*mp[len]);
if(a==b)fr=md;
else ngg=md;
}
// if(x==P(0,2))outp(P(to,fr));
chmax(ans,(to-fr+1)*len);
}
out(ans);
}
Compilation message
palindrome.cpp: In function 'vi manacher(std::string&)':
palindrome.cpp:60:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
60 | while(i<s.size()){
| ~^~~~~~~~~
palindrome.cpp:61:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
61 | while(i-j>=0&&i+j<s.size()&&s[i-j]==s[i+j])j++;
| ~~~^~~~~~~~~
palindrome.cpp: In function 'vi SA_IS(vi, int)':
palindrome.cpp:97:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
97 | for(int i = 1; i < str.size(); i++) {
| ~~^~~~~~~~~~~~
palindrome.cpp:111:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
111 | for(int i = 1; i < str.size(); i++) if(SA[i] != -1 && SL[SA[i]] == 0) { SA[i] = -1; }
| ~~^~~~~~~~~~~~
palindrome.cpp:123:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
123 | for(int j = SA[i]; j < SA.size(); j++) {
| ~~^~~~~~~~~~~
palindrome.cpp:154:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
154 | for(int i = 1; i < str.size(); i++) if(SA[i] != -1 && SL[SA[i]] == 0) { SA[i] = -1; }
| ~~^~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
372 KB |
Output is correct |
2 |
Correct |
1 ms |
256 KB |
Output is correct |
3 |
Correct |
1 ms |
256 KB |
Output is correct |
4 |
Correct |
1 ms |
256 KB |
Output is correct |
5 |
Correct |
1 ms |
256 KB |
Output is correct |
6 |
Correct |
0 ms |
256 KB |
Output is correct |
7 |
Correct |
1 ms |
256 KB |
Output is correct |
8 |
Correct |
1 ms |
256 KB |
Output is correct |
9 |
Correct |
1 ms |
256 KB |
Output is correct |
10 |
Correct |
1 ms |
384 KB |
Output is correct |
11 |
Correct |
0 ms |
256 KB |
Output is correct |
12 |
Correct |
1 ms |
256 KB |
Output is correct |
13 |
Correct |
1 ms |
256 KB |
Output is correct |
14 |
Correct |
1 ms |
256 KB |
Output is correct |
15 |
Correct |
1 ms |
256 KB |
Output is correct |
16 |
Correct |
0 ms |
256 KB |
Output is correct |
17 |
Correct |
0 ms |
372 KB |
Output is correct |
18 |
Correct |
0 ms |
256 KB |
Output is correct |
19 |
Correct |
1 ms |
384 KB |
Output is correct |
20 |
Correct |
1 ms |
384 KB |
Output is correct |
21 |
Correct |
1 ms |
384 KB |
Output is correct |
22 |
Correct |
1 ms |
384 KB |
Output is correct |
23 |
Correct |
1 ms |
256 KB |
Output is correct |
24 |
Correct |
1 ms |
384 KB |
Output is correct |
25 |
Correct |
1 ms |
384 KB |
Output is correct |
26 |
Correct |
1 ms |
384 KB |
Output is correct |
27 |
Correct |
1 ms |
384 KB |
Output is correct |
28 |
Correct |
1 ms |
384 KB |
Output is correct |
29 |
Correct |
1 ms |
384 KB |
Output is correct |
30 |
Correct |
1 ms |
384 KB |
Output is correct |
31 |
Correct |
1 ms |
384 KB |
Output is correct |
32 |
Correct |
1 ms |
384 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
544 KB |
Output is correct |
2 |
Correct |
1 ms |
512 KB |
Output is correct |
3 |
Correct |
1 ms |
384 KB |
Output is correct |
4 |
Correct |
1 ms |
512 KB |
Output is correct |
5 |
Correct |
1 ms |
384 KB |
Output is correct |
6 |
Correct |
1 ms |
372 KB |
Output is correct |
7 |
Correct |
1 ms |
512 KB |
Output is correct |
8 |
Correct |
1 ms |
512 KB |
Output is correct |
9 |
Correct |
1 ms |
512 KB |
Output is correct |
10 |
Correct |
2 ms |
512 KB |
Output is correct |
11 |
Correct |
1 ms |
512 KB |
Output is correct |
12 |
Correct |
1 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
1784 KB |
Output is correct |
2 |
Correct |
7 ms |
1784 KB |
Output is correct |
3 |
Correct |
5 ms |
1400 KB |
Output is correct |
4 |
Correct |
6 ms |
1528 KB |
Output is correct |
5 |
Correct |
9 ms |
1912 KB |
Output is correct |
6 |
Correct |
9 ms |
1784 KB |
Output is correct |
7 |
Correct |
7 ms |
1784 KB |
Output is correct |
8 |
Correct |
10 ms |
1656 KB |
Output is correct |
9 |
Correct |
9 ms |
1656 KB |
Output is correct |
10 |
Incorrect |
9 ms |
1656 KB |
Output isn't correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
72 ms |
14188 KB |
Output is correct |
2 |
Correct |
84 ms |
14948 KB |
Output is correct |
3 |
Correct |
45 ms |
10220 KB |
Output is correct |
4 |
Correct |
60 ms |
10988 KB |
Output is correct |
5 |
Correct |
155 ms |
13156 KB |
Output is correct |
6 |
Correct |
151 ms |
15596 KB |
Output is correct |
7 |
Correct |
99 ms |
12268 KB |
Output is correct |
8 |
Correct |
173 ms |
13744 KB |
Output is correct |
9 |
Correct |
144 ms |
13292 KB |
Output is correct |
10 |
Incorrect |
153 ms |
14060 KB |
Output isn't correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
268 ms |
43684 KB |
Output is correct |
2 |
Correct |
348 ms |
43700 KB |
Output is correct |
3 |
Correct |
149 ms |
32056 KB |
Output is correct |
4 |
Correct |
195 ms |
33212 KB |
Output is correct |
5 |
Correct |
833 ms |
46368 KB |
Output is correct |
6 |
Correct |
452 ms |
39584 KB |
Output is correct |
7 |
Correct |
432 ms |
38820 KB |
Output is correct |
8 |
Correct |
943 ms |
40604 KB |
Output is correct |
9 |
Execution timed out |
1037 ms |
40484 KB |
Time limit exceeded |
10 |
Halted |
0 ms |
0 KB |
- |