#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define mp make_pair
#define st first
#define nd second
#define ll long long
#define ull unsigned ll
#define pii pair<int,int>
#define pll pair<ll,ll>
#define vi vector<int>
const int mod=1000000007,mxn=1000010;
string s;
int n;
ull p=313;
ull hap[mxn];
ull hal[mxn];
ull pot[mxn];
ull gethp(int left,int right){
return hap[right]-hap[left-1]*pot[right-left+1];
}
ull gethl(int left,int right){
return hal[left]-hal[right+1]*pot[right-left+1];
}
ll acc[mxn];
ll ilz[mxn];
ll wie[mxn][26];
ll ans;
void liczsro(int x){
int mn=1;
int mx=min(x,n-x+1);
//cout <<mx <<" ";
while(mn<mx){
int sr=(mn+mx+1)/2;
if(gethp(x-sr+1,x)==gethl(x,x+sr-1)){
mn=sr;
}
else{
mx=sr-1;
}
}
//cout <<mn <<" ";
acc[x-mn]+=1;
acc[x]-=2;
acc[x+mn]+=1;
int baz=mn;
ans+=baz;
if(baz==min(x,n-x+1)){
//cout <<"0\n";
return;
}
mx=min(x,n-x+1);
mn=baz+1;
while(mn<mx){
int sr=(mn+mx+1)/2;
if(gethp(x-sr+1,x-baz-1) == gethl(x+baz+1,x+sr-1)){
mn=sr;
}
else{
mx=sr-1;
}
}
int dod=mn-baz;
//cout <<baz <<" "<<dod <<"\n";
char c1=s[x-baz-1]-'a';
char c2=s[x+baz-1]-'a';
wie[x-baz][c2]+=dod;
wie[x+baz][c1]+=dod;
//cout <<x <<" " <<baz <<" " <<c2+'a' <<"\n";
}
void liczd(int x){
int mn=0;
int mx=min(x,n-x);
while(mn<mx){
int sr=(mn+mx+1)/2;
if(gethp(x-sr+1,x)==gethl(x+1,x+sr)){
mn=sr;
}
else{
mx=sr-1;
}
}
//cout <<mn <<" ";
acc[x-mn]+=1;
acc[x]-=1;
acc[x+1]-=1;
acc[x+mn+1]+=1;
int baz=mn;
ans+=baz;
if(baz==min(x,n-x)){
//cout <<"0 ";
return;
}
mx=min(x,n-x);
mn=baz+1;
//cout <<mx <<" ";
while(mn<mx){
int sr=(mn+mx+1)/2;
if(gethp(x-sr+1,x-baz-1) == gethl(x+baz+2,x+sr)){
mn=sr;
}
else{
mx=sr-1;
}
}
int dod=mn-baz;
//cout <<dod <<" ";
char c1=s[x-baz-1]-'a';
char c2=s[x+baz]-'a';
wie[x-baz][c2]+=dod;
wie[x+baz+1][c1]+=dod;
//cout <<x-baz <<" " <<'a'+c2 <<"\n";
}
void pro(){
ll pr=0;
ll val=0;
for(int i=0;i<=n;i++){
ilz[i]=val;
pr+=acc[i];
val+=pr;
}
}
int main(){
cin >>s;
n=s.size();
pot[0]=1;
for(ull i=1;i<=mxn;i++){
pot[i]=pot[i-1]*p;
}
for(int i=0;i<n;i++){
hap[i+1]=hap[i]*p+s[i];
}
for(int i=n;i>0;i--){
hal[i]=hal[i+1]*p+s[i-1];
}
/*while(1){
int a,b;
cin >>a >>b;
cout <<gethp(a,b) <<"\n";
cout <<gethl(a,b) <<"\n";
}*/
for(int i=1;i<=n;i++){
liczsro(i);
}
//cout <<"\n";
for(int i=1;i<n;i++){
liczd(i);
}
//cout <<"\n";
pro();
//cout <<"\n";
/*for(int i=0;i<=n;i++){
cout <<acc[i] <<" ";
}
cout <<"\n";
*/
/*for(int i=0;i<=n;i++){
cout <<ilz[i] <<" ";
}*/
//cout <<ans<<"\n";
ll wyn=ans;
for(int i=1;i<=n;i++){
//cout <<ilz[i] <<" ";
for(int j=0;j<26;j++){
wyn=max(wyn,ans+wie[i][j]-ilz[i]+1);
}
}
//cout <<"\n";
/*for(int i=1;i<=n;i++){
ll x=0;
for(int j=0;j<26;j++){
x=max(x,wie[i][j]);
}
cout <<x<<" ";
}
cout <<"\n";*/
cout <<wyn;
}
Compilation message
palinilap.cpp: In function 'void liczsro(int)':
palinilap.cpp:67:15: warning: array subscript has type 'char' [-Wchar-subscripts]
wie[x-baz][c2]+=dod;
^
palinilap.cpp:68:15: warning: array subscript has type 'char' [-Wchar-subscripts]
wie[x+baz][c1]+=dod;
^
palinilap.cpp: In function 'void liczd(int)':
palinilap.cpp:111:15: warning: array subscript has type 'char' [-Wchar-subscripts]
wie[x-baz][c2]+=dod;
^
palinilap.cpp:112:17: warning: array subscript has type 'char' [-Wchar-subscripts]
wie[x+baz+1][c1]+=dod;
^
palinilap.cpp: In function 'int main()':
palinilap.cpp:129:9: warning: iteration 1000009 invokes undefined behavior [-Waggressive-loop-optimizations]
pot[i]=pot[i-1]*p;
~~~~~~^~~~~~~~~~~
palinilap.cpp:128:15: note: within this loop
for(ull i=1;i<=mxn;i++){
~^~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
11 ms |
8192 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
11 ms |
9344 KB |
Output is correct |
| 2 |
Correct |
9 ms |
9344 KB |
Output is correct |
| 3 |
Correct |
11 ms |
9344 KB |
Output is correct |
| 4 |
Incorrect |
12 ms |
8832 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
70 ms |
31992 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
