oj.uz

Submission #13187

# Submission time Handle Problem Language Result Execution time Memory
13187 2015-02-01T13:52:07 Z baneling100 Palindromes (APIO14_palindrome) C++
73 / 100
 1000 ms 76516 KB 
#include <stdio.h>
#include <algorithm>
#include <string.h>
#include <vector>
#define N_MAX 300000

using namespace std;

vector <int> PAL[2*N_MAX];
vector <int> PAL2[2*N_MAX+1];
int N, N_, MA[2*N_MAX], SA[2*N_MAX], LCP[2*N_MAX+1], STK[2][2*N_MAX], Top;
int Rank[4*N_MAX], Rtemp[4*N_MAX], Len, Loc[2*N_MAX];
long long Ans;
char S[2*N_MAX+1], S_[N_MAX+2];
bool comp1(int p, int q) {return S[p]<S[q];};
bool comp2(int p, int q) {return Rank[p]<Rank[q] || (Rank[p]==Rank[q] && Rank[p+Len]<Rank[q+Len]);};

void input(void) {

    int i;

    scanf("%s",&S_[1]);
    N_=strlen(&S_[1]);
    for(i=1 ; i<=N_ ; i++) {
        S[2*i-1]=S_[i];
        S[2*i  ]='#';
    }
    S[2*N_]=NULL;
    N=2*N_-1;
}

void manacher(void) {

    int i, j=0;

    for(i=1 ; i<=N ; i++) {
        i<=j+MA[j] ? MA[i]=min(j+MA[j]-i,MA[2*j-i]) : MA[i]=0;
        while(i+MA[i]+1<=N && S[i-MA[i]-1]==S[i+MA[i]+1]) MA[i]++;
        if(j+MA[j]<i+MA[i])
            j=i;
    }
}

void suffixArray(void) {

    int i;

    for(i=1 ; i<=N ; i++)
        SA[i]=i;
    sort(SA+1,SA+N+1,comp1);
    for(i=1 ; i<=N ; i++) {
        if(S[SA[i]]==S[SA[i-1]])
            Rank[SA[i]]=Rank[SA[i-1]];
        else
            Rank[SA[i]]=i;
    }
    for(Len=1 ; Len<N ; Len<<=1) {
        sort(SA+1,SA+N+1,comp2);
        for(i=1 ; i<=N ; i++) {
            if(Rank[SA[i]]>Rank[SA[i-1]] || (Rank[SA[i]]==Rank[SA[i-1]] && Rank[SA[i]+Len]>Rank[SA[i-1]+Len]))
                Rtemp[SA[i]]=i;
            else
                Rtemp[SA[i]]=Rtemp[SA[i-1]];
        }
        for(i=1 ; i<=N ; i++)
            Rank[i]=Rtemp[i];
    }
}

void longestCommonPrefix(void) {

    int i;

    for(i=1 ; i<=N ; i++)
        Loc[SA[i]]=i;
    for(i=1 ; i<=N ; i++) {
        if(LCP[Loc[i-1]])
            LCP[Loc[i]]=LCP[Loc[i-1]]-1;
        while(S[i+LCP[Loc[i]]]==S[SA[Loc[i]-1]+LCP[Loc[i]]]) LCP[Loc[i]]++;
    }
}

void calculate(void) {

    int i, j=0, k, p;

    for(i=1 ; i<=N ; i++)
        while(j+1<=i+MA[i]) {
            j++;
            PAL[Loc[2*i-j]].push_back(2*(j-i)+1);
        }
    STK[0][Top]=-1;
    for(i=1 ; i<=N ; i++) {
        while(STK[0][Top]>=LCP[i]) Top--;
        STK[0][++Top]=LCP[i];
        STK[1][  Top]=i;
        k=PAL[i].size();
        for(j=0 ; j<k ; j++) {
            p=lower_bound(STK[0]+1,STK[0]+Top+1,PAL[i][j])-STK[0]-1;
            PAL2[STK[1][p]].push_back(PAL[i][j]);
        }
    }
    for(i=1 ; i<=N ; i++)
        sort(PAL2[i].begin(),PAL2[i].end());
    Top=0;
    for(i=1 ; i<=N+1 ; i++) {
        while(STK[0][Top]>LCP[i]) {
            if(S[SA[STK[1][Top]]]=='#') {
                if(Ans<(long long)(STK[0][Top]/2)*(i-STK[1][Top]))
                    Ans=(long long)(STK[0][Top]/2)*(i-STK[1][Top]);
            }
            else
                if(Ans<(long long)((STK[0][Top]+1)/2)*(i-STK[1][Top]))
                    Ans=(long long)((STK[0][Top]+1)/2)*(i-STK[1][Top]);
            Top--;
        }
        k=PAL2[i].size();
        for(j=0 ; j<k ; j++) {
            if(j>0 && PAL2[i][j]==PAL2[i][j-1])
                continue;
            STK[0][++Top]=PAL2[i][j];
            STK[1][  Top]=i;
        }
    }
}

int main(void) {

    input();
    manacher();
    suffixArray();
    longestCommonPrefix();
    calculate();
    printf("%lld",Ans);

    return 0;
}

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 53660 KB Output is correct - answer is '7'
2 Correct 3 ms 53660 KB Output is correct - answer is '4'
3 Correct 8 ms 53660 KB Output is correct - answer is '9'
4 Correct 3 ms 53660 KB Output is correct - answer is '1'
5 Correct 11 ms 53660 KB Output is correct - answer is '1'
6 Correct 4 ms 53660 KB Output is correct - answer is '2'
7 Correct 11 ms 53660 KB Output is correct - answer is '3'
8 Correct 3 ms 53660 KB Output is correct - answer is '3'
9 Correct 4 ms 53660 KB Output is correct - answer is '15'
10 Correct 4 ms 53660 KB Output is correct - answer is '24'
11 Correct 7 ms 53660 KB Output is correct - answer is '10'
12 Correct 3 ms 53660 KB Output is correct - answer is '24'
13 Correct 4 ms 53660 KB Output is correct - answer is '25'
14 Correct 7 ms 53660 KB Output is correct - answer is '28'
15 Correct 3 ms 53660 KB Output is correct - answer is '2'
16 Correct 0 ms 53660 KB Output is correct - answer is '1'
17 Correct 3 ms 53660 KB Output is correct - answer is '15'
18 Correct 0 ms 53660 KB Output is correct - answer is '18'
19 Correct 3 ms 53660 KB Output is correct - answer is '1176'
20 Correct 5 ms 53660 KB Output is correct - answer is '1225'
21 Correct 3 ms 53660 KB Output is correct - answer is '136'
22 Correct 7 ms 53660 KB Output is correct - answer is '45'
23 Correct 11 ms 53660 KB Output is correct - answer is '2500'
24 Correct 4 ms 53660 KB Output is correct - answer is '380'
25 Correct 3 ms 53660 KB Output is correct - answer is '2304'
26 Correct 4 ms 53660 KB Output is correct - answer is '110'
27 Correct 0 ms 53660 KB Output is correct - answer is '93'
28 Correct 3 ms 53660 KB Output is correct - answer is '729'
29 Correct 8 ms 53660 KB Output is correct - answer is '132'
30 Correct 3 ms 53660 KB Output is correct - answer is '7'
31 Correct 3 ms 53660 KB Output is correct - answer is '8'
32 Correct 3 ms 53660 KB Output is correct - answer is '64'

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 53660 KB Output is correct - answer is '124251'
2 Correct 9 ms 53660 KB Output is correct - answer is '38226'
3 Correct 6 ms 53660 KB Output is correct - answer is '249500'
4 Correct 6 ms 53660 KB Output is correct - answer is '5778'
5 Correct 4 ms 53660 KB Output is correct - answer is '247506'
6 Correct 10 ms 53660 KB Output is correct - answer is '248004'
7 Correct 7 ms 53660 KB Output is correct - answer is '973'
8 Correct 0 ms 53660 KB Output is correct - answer is '123753'
9 Correct 9 ms 53660 KB Output is correct - answer is '2346'
10 Correct 9 ms 53660 KB Output is correct - answer is '53'
11 Correct 6 ms 53660 KB Output is correct - answer is '52'
12 Correct 4 ms 53660 KB Output is correct - answer is '976'

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 54348 KB Output is correct - answer is '12497500'
2 Correct 35 ms 53924 KB Output is correct - answer is '6481800'
3 Correct 34 ms 54340 KB Output is correct - answer is '25000000'
4 Correct 38 ms 54248 KB Output is correct - answer is '17816841'
5 Correct 37 ms 54584 KB Output is correct - answer is '9945'
6 Correct 45 ms 54320 KB Output is correct - answer is '504100'
7 Correct 41 ms 53924 KB Output is correct - answer is '1512930'
8 Correct 32 ms 54320 KB Output is correct - answer is '413'
9 Correct 34 ms 54320 KB Output is correct - answer is '428'
10 Correct 43 ms 54452 KB Output is correct - answer is '7232'

Subtask #4
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 407 ms 60904 KB Output is correct - answer is '1249925001'
2 Correct 417 ms 60908 KB Output is correct - answer is '396337935'
3 Correct 401 ms 60892 KB Output is correct - answer is '2500050000'
4 Correct 395 ms 57736 KB Output is correct - answer is '1016525689'
5 Correct 510 ms 63956 KB Output is correct - answer is '99645'
6 Correct 488 ms 59804 KB Output is correct - answer is '78569380'
7 Correct 448 ms 60192 KB Output is correct - answer is '82810000'
8 Correct 508 ms 60320 KB Output is correct - answer is '3989'
9 Correct 493 ms 60688 KB Output is correct - answer is '125529616'
10 Correct 514 ms 62504 KB Output is correct - answer is '66664'

Subtask #5
0.0 / 27.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1000 ms 76516 KB Program timed out
2 Halted 0 ms 0 KB -