#include <bits/stdc++.h>
using namespace std;
const int mx=5005;
char a[mx],S[mx<<1];
int dp[mx<<1], Z, r,p,np;
void input(){
ios_base::sync_with_stdio(false);
scanf("%s",a);
int N=strlen(a);
int i=0;
for(int k=0;k<N;k++){
S[++i]=a[k];
S[++i]='*';
}
Z=2*N-1;
}
int Manacher(int t, char c){
r=p=np=0; //p=np
char x=S[t];
S[t]=c;
memset(dp,0,sizeof(dp));
for(int i=1;i<=Z;i++){
dp[i]=(i>r)?0:min(dp[2*p-i],r-i);
for(;i+dp[i]+1<=Z && S[i+dp[i]+1]==S[i-dp[i]-1];++dp[i]);
if(i+dp[i]>r) p=i,r=i+dp[i];
if(!dp[i]) np+=(S[i]=='*'?0:1);
else if(dp[i]==i-1||dp[i]+i==Z) np+=(S[i]=='*'?(dp[i]+1)>>1:(dp[i]+2)>>1);
else np+=(S[i]=='*'?(dp[i]>>1):(dp[i]+1)>>1);
}
S[t]=x;
return np;
}
int main(){
input();
int X=0;
for(int i=1;i<=Z;i+=2){
for(char x='a';x<='z';x++){
/*
if(X<Manacher(i,x)){
swap(S[i],x);
puts(S+1);
swap(S[i],x);
for(int i=1;i<=Z;i++) printf("%d",dp[i]);
puts("");
}*/
X=max(X,Manacher(i,x));
}
}
printf("%d\n",X);
}
Compilation message
palinilap.cpp: In function 'void input()':
palinilap.cpp:8:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%s",a);
^
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
2232 KB |
Output is correct |
2 |
Correct |
6 ms |
2232 KB |
Output is correct |
3 |
Correct |
6 ms |
2232 KB |
Output is correct |
4 |
Correct |
6 ms |
2232 KB |
Output is correct |
5 |
Correct |
6 ms |
2232 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
1000 ms |
2232 KB |
Execution timed out |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
0 ms |
2232 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |