Submission #926558

#	Time	Username	Problem	Language	Result	Execution time	Memory
926558		boyliguanhan	Palindromes (APIO14_palindrome)	C++17	100 / 100	39 ms	70876 KiB

palindrome

#include<bits/stdc++.h>
#define N 300100
using namespace std;
long long S[N],ans,c,m;
struct T {
    long long t[N][26],li[N],len[N],oc[N],sz,lst;
    T(){sz=li[0]=li[1]=1;len[1]=-1;}
    void add(int c) {
        int p = lst;S[++m]=c;
        while (S[m-1-len[p]]-c)p=li[p];
        if (!t[p][c]) {
            int q=li[p];
            while(S[m-len[q]-1]-c)q=li[q];
            li[++sz]=t[q][c];
            len[t[p][c]=sz]=len[p]+2;
        }
        oc[lst=t[p][c]]++;
    }
} X; 
int main() {
    memset(S,1,sizeof S);
    c=getchar();
    while(c!='\n') X.add(c-'a'),c=getchar();
    for(int x=X.sz;~x;x--)
        X.oc[X.li[x]]+=X.oc[x];
    for(int x=X.sz;~x;x--)
        ans=max(ans,X.len[x]*X.oc[x]);
    cout<<ans<<'\n';
}

• Subtask 1: 8 / 8
• Subtask 2: 15 / 15
• Subtask 3: 24 / 24
• Subtask 4: 26 / 26
• Subtask 5: 27 / 27