oj.uz

Submission #670818

# Submission time Handle Problem Language Result Execution time Memory
670818 2022-12-10T17:48:03 Z fatemetmhr Palindromes (APIO14_palindrome) C++17
100 / 100
 965 ms 107252 KB 
// ~ Be Name Khoda ~ 
 
#include <bits/stdc++.h>

#pragma GCC optimize ("Ofast")
#pragma GCC target("avx2")
#pragma GCC optimize("unroll-loops")
 
using namespace std;
 
typedef long long ll;
 
#define all(x) x.begin(), x.end()
#define pb     push_back
#define fi     first
#define se     second
 
const int maxn5 = 3e5 + 10;
const int lg    = 19;
const ll  inf   = 1e18;
const int al    = 200;
 
int rnk[lg][maxn5], a[maxn5], lef[maxn5], rig[maxn5];
int val[maxn5], mn[maxn5], lcp[maxn5], rev[maxn5];
int cmpid, lenlen, cmpsz, z[2][maxn5];
set <int> av[2];
vector <int> srt[maxn5];
vector <pair<int, int>> ed;
vector <pair<int, pair<int, int>>> have;
vector <pair<pair<int, int>, int>> req;
 
inline int get_lcp(int v, int u){
    int ans = 0;
    for(int i = lg - 1; i >= 0; i--) if(rnk[i][u] == rnk[i][v]){
        u += (1 << i);
        v += (1 << i);
        ans += (1 << i);
    }
    return ans;
}
 
inline void fix2(int& a){
    if(a < 0)
        a += cmpsz;
    if(a >= cmpsz)
        a -= cmpsz;
}

inline int fix(int a){
    if(a >= cmpsz)
        a -= cmpsz;
    return a;
}
 
inline bool cmp(int i, int j){
    return rnk[cmpid][i] < rnk[cmpid][j] || (rnk[cmpid][i] == rnk[cmpid][j] && rnk[cmpid][fix(i + lenlen)] < rnk[cmpid][fix(j + lenlen)]);
}
 
inline void sort1(int n){
    for(int i = 0; i < max(n, al); i++)
        srt[i].clear();
    for(int i = 0; i < n; i++)
        srt[rnk[cmpid][fix(i + lenlen)]].pb(i);
    int pt = 0;
    for(int i = 0; i < max(n, al); i++)
        for(auto u : srt[i])
            a[pt++] = u;
}
 
inline void sort(){
    int n = cmpsz;
    for(int i = 0; i < n; i++)
        srt[rnk[cmpid][a[i]]].pb(a[i]);
    int pt = 0;
    for(int i = 0; i < max(n, al); i++){
        for(auto u : srt[i])
            a[pt++] = u;
        srt[i].clear();
    }
}
 
inline void build_sf(string s){
    s.pb('#');
    int n = cmpsz = s.size();
    for(int i = 0; i < n; i++){
        rnk[0][i] = int(s[i]);
        srt[rnk[0][i]].pb(i);
    }
    int pt = 0;
    for(int i = 0; i < al; i++) for(auto u : srt[i])
        a[pt++] = u;
    for(int i = 0; i < al; i++)
        srt[i].clear();
    for(int j = 1; j < lg; j++){
        cmpid = j - 1; lenlen = (1 << cmpid) % n;
        for(int i = 0; i < n; i++)
            fix2(a[i] = a[i] - lenlen);
        sort();
        rnk[j][a[0]] = 0;
        for(int i = 1; i < n; i++){
            rnk[j][a[i]] = rnk[j][a[i - 1]] + cmp(a[i - 1], a[i]);
        }
    }
}
 
 
int main(){
    ios_base::sync_with_stdio(false); cin.tie(0);
 
    string s; cin >> s;
    int n = s.size();
 
    build_sf(s);
    for(int i = 0; i < n; i++)
        a[i] = a[i + 1];
 
    for(int i = 1; i < n; i++){
        lcp[i] = get_lcp(a[i - 1], a[i]);
        ed.pb({lcp[i], i});
    }
    ll ans = 0;
    //cout << t << endl;
    for(int i = 0; i < n; i++){
        //cout << a[i] << ' ';
        rev[a[i]] = i;
        lef[i] = rig[i] = i;
    }
 
    int l = 0, r = 0;
    for(int i = 0; i < n; i++){
        if(i){
            if(r >= i)
                z[1][i] = min(r - i + 1, z[1][r + l - i + 1]);
            while(z[1][i] + i < n && i - z[1][i] - 1 >= 0 && s[i + z[1][i]] == s[i - z[1][i] - 1])
                z[1][i]++;
            have.pb({i - z[1][i], {1, i - 1}});
            ans = max(ans, z[1][i] * 2LL);
            if(i + z[1][i] - 1 > r){
                r = i + z[1][i] - 1;
                l = i - z[1][i];
            }
        }
        if(r >= i)
            z[0][i] = min(r - i + 1, z[0][r + l - i]);
        while(z[0][i] + i < n && i - z[0][i] >= 0 && s[i + z[0][i]] == s[i - z[0][i]])
            z[0][i]++;
        have.pb({i - z[0][i] + 1, {0, i}});
        if(i + z[0][i] - 1 > r){
            r = i + z[0][i] - 1;
            l = i - z[0][i] + 1;
        }
        ans = max(ans, z[0][i] * 2LL - 1);
    }
 
    sort(all(ed));
    while(ed.size()){
        int id = ed.back().se, len = ed.back().fi;
        ed.pop_back();
        int l, r;
        lef[rig[id]] = l = lef[id - 1];
        rig[lef[id - 1]] = r = rig[id];
        req.pb({{a[l], len}, r - l + 1});
    }
 
    sort(all(req));
    sort(all(have));
    int ind = 0;
    //cout << "having " << ans << endl;
 
    for(auto [b, val] : req){
        int l = b.fi, len = b.se;
        //cout << "A request of " << l << ' ' << len << ' ' << val << endl;
        while(ind < have.size() && have[ind].fi <= l){
            av[have[ind].se.fi].insert(have[ind].se.se);
            //cout << "adding " << have[ind].fi << ' ' << have[ind].se.fi << ' ' << have[ind].se.se << endl;
            ind++;
        }
        int klen = len / 2;
        int slen = klen + len % 2;
        auto it = av[0].upper_bound(l + slen - 1);
        if(av[0].size() && it != av[0].begin()){
            it--;
            ans = max(ans, ll(val) * (((*it) - l) * 2 + 1));
            //cout << "well fard " << (*it) << ' ' << ans << endl;
        }
        it = av[1].upper_bound(l + klen - 1);
        if(av[1].size() && it != av[1].begin()){
            it--;
            ans = max(ans, ll(val) * ((*it) - l + 1) * 2);
            //cout << "well zoj " << (*it) << ' ' << ans << endl;
        }
    }
 
    cout << ans << endl;
 
}

/*
Why so fast...? 
Hold on...
Hold your breath...
Need anything else?

Nein, Kein Problem...
Das Leben war schon immer so grausam :)
*/

Compilation message

palindrome.cpp: In function 'int main()':
palindrome.cpp:173:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  173 |         while(ind < have.size() && have[ind].fi <= l){
      |               ~~~~^~~~~~~~~~~~~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 7508 KB Output is correct
2 Correct 4 ms 7508 KB Output is correct
3 Correct 4 ms 7508 KB Output is correct
4 Correct 3 ms 7508 KB Output is correct
5 Correct 4 ms 7508 KB Output is correct
6 Correct 4 ms 7508 KB Output is correct
7 Correct 4 ms 7508 KB Output is correct
8 Correct 3 ms 7508 KB Output is correct
9 Correct 3 ms 7508 KB Output is correct
10 Correct 4 ms 7508 KB Output is correct
11 Correct 4 ms 7508 KB Output is correct
12 Correct 4 ms 7508 KB Output is correct
13 Correct 4 ms 7508 KB Output is correct
14 Correct 4 ms 7508 KB Output is correct
15 Correct 4 ms 7508 KB Output is correct
16 Correct 4 ms 7508 KB Output is correct
17 Correct 4 ms 7508 KB Output is correct
18 Correct 3 ms 7508 KB Output is correct
19 Correct 4 ms 7508 KB Output is correct
20 Correct 4 ms 7508 KB Output is correct
21 Correct 4 ms 7508 KB Output is correct
22 Correct 3 ms 7508 KB Output is correct
23 Correct 4 ms 7508 KB Output is correct
24 Correct 4 ms 7508 KB Output is correct
25 Correct 4 ms 7508 KB Output is correct
26 Correct 4 ms 7508 KB Output is correct
27 Correct 4 ms 7664 KB Output is correct
28 Correct 5 ms 7508 KB Output is correct
29 Correct 4 ms 7508 KB Output is correct
30 Correct 4 ms 7508 KB Output is correct
31 Correct 4 ms 7508 KB Output is correct
32 Correct 4 ms 7508 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 7764 KB Output is correct
2 Correct 5 ms 7764 KB Output is correct
3 Correct 4 ms 7764 KB Output is correct
4 Correct 5 ms 7764 KB Output is correct
5 Correct 5 ms 7764 KB Output is correct
6 Correct 5 ms 7764 KB Output is correct
7 Correct 5 ms 7764 KB Output is correct
8 Correct 4 ms 7764 KB Output is correct
9 Correct 5 ms 7764 KB Output is correct
10 Correct 5 ms 7764 KB Output is correct
11 Correct 5 ms 7764 KB Output is correct
12 Correct 5 ms 7764 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 10856 KB Output is correct
2 Correct 13 ms 10512 KB Output is correct
3 Correct 14 ms 10776 KB Output is correct
4 Correct 13 ms 10712 KB Output is correct
5 Correct 17 ms 10588 KB Output is correct
6 Correct 15 ms 10564 KB Output is correct
7 Correct 13 ms 10544 KB Output is correct
8 Correct 17 ms 10268 KB Output is correct
9 Correct 16 ms 10332 KB Output is correct
10 Correct 15 ms 10448 KB Output is correct

Subtask #4
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 120 ms 40848 KB Output is correct
2 Correct 118 ms 39240 KB Output is correct
3 Correct 118 ms 40744 KB Output is correct
4 Correct 118 ms 40452 KB Output is correct
5 Correct 141 ms 38952 KB Output is correct
6 Correct 142 ms 40148 KB Output is correct
7 Correct 128 ms 39676 KB Output is correct
8 Correct 204 ms 35628 KB Output is correct
9 Correct 174 ms 36576 KB Output is correct
10 Correct 152 ms 39216 KB Output is correct

Subtask #5
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 375 ms 94756 KB Output is correct
2 Correct 367 ms 106924 KB Output is correct
3 Correct 381 ms 103616 KB Output is correct
4 Correct 370 ms 104124 KB Output is correct
5 Correct 488 ms 107252 KB Output is correct
6 Correct 430 ms 104248 KB Output is correct
7 Correct 453 ms 103616 KB Output is correct
8 Correct 958 ms 91552 KB Output is correct
9 Correct 965 ms 91484 KB Output is correct
10 Correct 570 ms 101892 KB Output is correct
11 Correct 355 ms 100496 KB Output is correct
12 Correct 877 ms 92864 KB Output is correct