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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#273861#7876. Cyclic Substringsucup-team992#TL 575ms565196kbC++174.7kb2023-12-03 04:48:272023-12-03 04:48:27

Judging History

你现在查看的是最新测评结果

  • [2023-12-03 04:48:27]
  • 评测
  • 测评结果:TL
  • 用时:575ms
  • 内存:565196kb
  • [2023-12-03 04:48:27]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define ll long long
typedef int uci;
#define int long long
#define F first
#define S second
#define ar array
string s;
const int MOD = 1e9+7;
int fhash[9000001];
int bhash[9000001];
int inv[9000001];
int pows[9000001];
seed_seq seq{
    (uint64_t) chrono::duration_cast<chrono::nanoseconds>(chrono::high_resolution_clock::now().time_since_epoch()).count(),
    (uint64_t) __builtin_ia32_rdtsc(),
    (uint64_t) (uintptr_t) make_unique<char>().get()
};
mt19937 rng(seq);
int p;
int exp(int n, int pe){
    int out{1};
    while(pe){
        if(pe&1){
            out *= n;
            out %= MOD;
        }
        pe >>= 1;
        n *= n;
        n %= MOD;
    }
    return out;
}
int ms;
void init(){
    int run{};
    int pow = 1;
    inv[0] = 1;
    inv[1] = exp(p, MOD-2);
    pows[0] = 1;
    pows[1] = p;
    for(int i{}; i < s.size(); ++i){
        if(i >= 2){
            inv[i] = (inv[i-1]*inv[1])%MOD;
            pows[i] = (pows[i-1]*p)%MOD;
        }
        run += (pows[i]*(s[i]-'0'+1))%MOD;
        run %= MOD;
        fhash[i] = run;
    }

    run = 0;
    for(int i = s.size()-1; i >= 0; --i){
        run += (pows[ms-1-i]*(s[i]-'0'+1))%MOD;
        run %= MOD;
        bhash[i] = run;
    }
}
bool eq(int i, int j){
    int fh = ((fhash[j] - (i == 0 ? 0 : fhash[i-1]))*inv[i])%MOD;
    fh %= MOD;
    if(fh < 0)
        fh += MOD;
    int bh = ((bhash[i] - (j == ms-1 ? 0 : bhash[j+1]))*inv[ms-1-j])%MOD;
    bh %= MOD;
    if(bh < 0)
        bh += MOD;
    return fh == bh;
}

int gethash(int i, int j){
    int fh = ((fhash[j] - (i == 0 ? 0 : fhash[i-1]))*inv[i])%MOD;
    fh %= MOD;
    if(fh < 0)
        fh += MOD;
    return fh;
}
template <class K, class V>
using ht = gp_hash_table<
    K, V, hash<K>, equal_to<K>, direct_mask_range_hashing<>, linear_probe_fn<>,
    hash_standard_resize_policy<hash_exponential_size_policy<>,
                                hash_load_check_resize_trigger<>, true>>;
int pcounts[9000001];
int things[9000001];
int isp[9000001];
vector<int> plengths[3000001];
struct node{
    node *ne[10];
    int ind;
    node(){
        for(int i{}; i < 10; ++i)
            ne[i] = nullptr;
        ind = -1;
    }
};

int add(int i, int pl, node *root){
    if(i == 0){
        if(root->ind != -1)
            return root->ind;
        root->ind = pl;
        return root->ind;
    }else{
        if(!root->ne[i%10]){
            root->ne[i%10] = new node();
        }
        return add(i/10, pl, root->ne[i%10]);
    }
}


void solve(){
    p = uniform_int_distribution<int>(11, MOD-2)(rng);
    int n;
    cin >> n;
    cin >> s;

    string t = s;
    s += t;
    s += t;
    ms = s.size();
    init();
    int ind{};
    node *root = new node();
    for(int i = n; i < 2*n; ++i){
        int l = 1, r = (n-1)/2;
        int longest = 0;
        while(l <= r){
            int mid = l + (r-l)/2;
            if(eq(i-mid, i+mid)){
                longest = mid;
                l = mid+1;
            }else{
                r = mid-1;
            }
        }
        int hh = gethash(i-longest, i+longest);
        int le = 1+2*longest;
        int place = add(hh, ind, root);
        if(place == ind){
            plengths[le].push_back(place);
            ind++;
        }
        pcounts[place]++;
        isp[place] = i;

        l = 1, r = n/2;
        longest = 0;
        while(l <= r){
            int mid = l + (r-l)/2;
            if(eq(i-mid+1, i+mid)){
                longest = mid;
                l = mid+1;
            }else
                r = mid-1;
        }
        if(longest != 0){
            hh = gethash(i-longest+1, i+longest);
            le = 2*longest;
            place = add(hh, ind, root);
            if(place == ind){
                plengths[le].push_back(place);
                ind++;
            }
            pcounts[place]++;
            isp[place] = i;
        }
    }

    int out{};
    int mm = 998244353;
    for(int i = n; i >= 1; --i){
        for(int j : plengths[i]){
            out += ((pcounts[j]*pcounts[j])%mm * i)%mm;
            out %= mm;
            if(i > 2){
                int hh;
                if(i%2 == 0){
                    hh = gethash(isp[j]-(i-2)/2+1, isp[j]+(i-2)/2);
                }else{
                    hh = gethash(isp[j]-(i-2)/2, isp[j]+(i-2)/2);
                }
                int place = add(hh, ind, root);
                if(place == ind){
                    plengths[i-2].push_back(place);
                    ind++;
                }
                pcounts[place] += pcounts[j];
                isp[place] = isp[j];
            }
        }
    }
    cout << out << '\n';
}

uci main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    solve();
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 11ms
memory: 84688kb

input:

5
01010

output:

39

result:

ok 1 number(s): "39"

Test #2:

score: 0
Accepted
time: 4ms
memory: 85920kb

input:

8
66776677

output:

192

result:

ok 1 number(s): "192"

Test #3:

score: 0
Accepted
time: 7ms
memory: 85520kb

input:

1
1

output:

1

result:

ok 1 number(s): "1"

Test #4:

score: 0
Accepted
time: 8ms
memory: 85124kb

input:

2
22

output:

12

result:

ok 1 number(s): "12"

Test #5:

score: 0
Accepted
time: 3ms
memory: 85304kb

input:

2
21

output:

2

result:

ok 1 number(s): "2"

Test #6:

score: 0
Accepted
time: 7ms
memory: 84608kb

input:

3
233

output:

10

result:

ok 1 number(s): "10"

Test #7:

score: 0
Accepted
time: 19ms
memory: 85008kb

input:

3
666

output:

54

result:

ok 1 number(s): "54"

Test #8:

score: 0
Accepted
time: 575ms
memory: 565196kb

input:

1000000
3333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333...

output:

496166704

result:

ok 1 number(s): "496166704"

Test #9:

score: -100
Time Limit Exceeded

input:

3000000
2222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222...

output:

890701718

result: