oj.uz

답안 #47587

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
47587 2018-05-05T06:51:31 Z TAMREF 회문 (APIO14_palindrome) C++11
23 / 100
 1000 ms 15040 KB 
#include <bits/stdc++.h>
//#define TAMREF 1
using namespace std;

typedef long long ll;

const char g = 'a' + 26;
const ll o = 28LL;
const ll h[2] = {1000000007LL, 1610612741LL};
const ll io[2] = {35714286LL, 1323003323LL};
const int mx = 6e5 + 5;



ll ph[2][mx], iph[2][mx];

void init_hash(){
    for(int b = 0; b < 2; b++){
        ph[b][0] = 1;
        iph[b][0] = 1;
        for(int i = 1; i < mx; i++){
            ph[b][i] = ph[b][i-1] * o % h[b];
            if(i <= 2) iph[b][i] = iph[b][i-1] * io[b] % h[b];
        }
    }
}

char S[mx], P[mx];
int n, m;

void input(){
    scanf("%s",P); m = strlen(P);
    for(int i = 0; i < m; i++){
        S[2*i] = g;
        S[2*i+1] = P[i];
    }
    S[2*m] = g;
    n = 2 * m + 1;
}

int R[mx];

void Manacher(){
    int r = 0, j = 0;
    for(int i = 1; i < n; i++){
        int &h = R[i];
        if(i <= r) h = min(r - i, R[2*j - i]);
        while(i-h-1 >= 0 && i+h+1 < n && S[i-h-1] == S[i+h+1]) ++h;
        if(i + h > r){
            j = i;
            r = i + h;
        }
    }
    #ifdef TAMREF
    puts(S);
    for(int i = 0; i < n; i++) printf("%d ",R[i]);
    puts("");
    #endif
}

unordered_map<ll,int> I;
vector<int> cnt(1);
vector<int> len(1);
vector<vector<int>> gph(1);
vector<int> isRoot(1);

void Shrink(){
    for(int i = 0; i < n; i++) S[i] -= 'a'-1;

    for(int i = 1, s, e; i < n-1; i++){
        if(!R[i]) continue;
        s = i - R[i] + 1, e = i + R[i] - 1;

        ll hv[2] = {0,0}, tmp;
        int child_i = -1;
        int tmp_i;
        int flag_once = 1, keep_loop = 1;

        for(int b = 0; b < 2; b++){
            for(int j = s; j <= e; j++){
                hv[b] = (hv[b] * o + S[j]) % h[b];
            }
        }

        while(e >= s){
            tmp = (hv[0] << 32 | hv[1]);
            tmp_i = I[tmp];
            if(!tmp_i){ //insert new hash value
                #ifdef TAMREF
                printf("%d-th HASH : [%d, %d],\nhash string = ",cnt.size(),s,e);
                for(int j = s; j <= e; j++) printf("%c",S[j] + 'a' - 1);
                puts("");
                #endif // TAMREF
                tmp_i = I[tmp] = cnt.size();
                cnt.push_back(flag_once);
                len.push_back((e-s)/2 + 1);
                gph.push_back(vector<int>());
                isRoot.push_back(1);
            }else{
                cnt[tmp_i] += flag_once;
                keep_loop = 0;
            }

            flag_once = 0;

            if(child_i != -1){
                gph[tmp_i].push_back(child_i);
                isRoot[child_i] = 0;
            }

            if(!keep_loop || e - 2 < s + 2) break;

            child_i = tmp_i;
            for(int b = 0; b < 2; b++){
                hv[b] -= (S[e] + o * S[e-1] + ph[b][e-s] * S[s] + ph[b][e-s-1] * S[s+1]) % h[b];
                hv[b] = (hv[b] * iph[b][2] % h[b] + h[b]) % h[b];
            }
            e -= 2;
            s += 2;
        }
    }
}

int vis[mx];
ll ans = 1;

int dfs(int x){
    #ifdef TAMREF
    printf("dfs : %d\n",x);
    #endif // TAMREF
    ll c = cnt[x];
    vis[x] = 1;
    for(int &u : gph[x]){
        if(!vis[u]) c += dfs(u);
    }
    ans = max(ans, c * len[x]);
    return c;
}

void pro(){
    int N = cnt.size();
    for(int i = 1; i < N; i++){
        #ifdef TAMREF
        printf("%d - th node : cnt = %d, len = %d, isRoot = %d\n",i,cnt[i],len[i],isRoot[i]);
        #endif // TAMREF
        if(isRoot[i] && !vis[i]){
            #ifdef TAMREF
            printf("dfs start on %d\n",i);
            #endif // TAMREF
            dfs(i);
        }
    }
    printf("%lld\n",ans);
}

int main(){
    init_hash();
    input();
    Manacher();
    Shrink();
    pro();
}

Compilation message

palindrome.cpp: In function 'void input()':
palindrome.cpp:32:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%s",P); m = strlen(P);
     ~~~~~^~~~~~~~

Subtask #1
8.0 / 8.0

# 결과 실행 시간 메모리 Grader output
1 Correct 16 ms 9720 KB Output is correct
2 Correct 17 ms 9832 KB Output is correct
3 Correct 16 ms 9832 KB Output is correct
4 Correct 16 ms 9832 KB Output is correct
5 Correct 16 ms 9832 KB Output is correct
6 Correct 16 ms 9980 KB Output is correct
7 Correct 16 ms 9980 KB Output is correct
8 Correct 16 ms 10048 KB Output is correct
9 Correct 16 ms 10048 KB Output is correct
10 Correct 17 ms 10048 KB Output is correct
11 Correct 16 ms 10048 KB Output is correct
12 Correct 17 ms 10048 KB Output is correct
13 Correct 16 ms 10048 KB Output is correct
14 Correct 17 ms 10048 KB Output is correct
15 Correct 17 ms 10048 KB Output is correct
16 Correct 16 ms 10048 KB Output is correct
17 Correct 16 ms 10048 KB Output is correct
18 Correct 17 ms 10048 KB Output is correct
19 Correct 16 ms 10048 KB Output is correct
20 Correct 17 ms 10048 KB Output is correct
21 Correct 16 ms 10048 KB Output is correct
22 Correct 16 ms 10048 KB Output is correct
23 Correct 16 ms 10048 KB Output is correct
24 Correct 17 ms 10048 KB Output is correct
25 Correct 18 ms 10048 KB Output is correct
26 Correct 16 ms 10048 KB Output is correct
27 Correct 17 ms 10048 KB Output is correct
28 Correct 16 ms 10048 KB Output is correct
29 Correct 16 ms 10048 KB Output is correct
30 Correct 16 ms 10048 KB Output is correct
31 Correct 16 ms 10048 KB Output is correct
32 Correct 16 ms 10048 KB Output is correct

Subtask #2
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 29 ms 10048 KB Output is correct
2 Correct 22 ms 10048 KB Output is correct
3 Correct 41 ms 10048 KB Output is correct
4 Correct 21 ms 10048 KB Output is correct
5 Correct 41 ms 10160 KB Output is correct
6 Correct 41 ms 10160 KB Output is correct
7 Correct 17 ms 10160 KB Output is correct
8 Correct 30 ms 10208 KB Output is correct
9 Correct 18 ms 10216 KB Output is correct
10 Correct 16 ms 10216 KB Output is correct
11 Correct 16 ms 10216 KB Output is correct
12 Correct 16 ms 10216 KB Output is correct

Subtask #3
0 / 24.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 1086 ms 11472 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 26.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 1078 ms 12524 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #5
0 / 27.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 1084 ms 15040 KB Time limit exceeded
2 Halted 0 ms 0 KB -