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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#561107 | #7876. Cyclic Substrings | HJR | ML | 507ms | 1048076kb | C++23 | 2.4kb | 2024-09-12 20:10:01 | 2024-09-12 20:10:05 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
#define endl "\n"
#define debug(x) cout<<#x<<": "<<x<<endl
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
using ll=long long;
using ull=unsigned long long;
// #define int long long
const int mo=998244353;
struct Node{
int cnt;
int len;
int fail;
char s;
vector<int> next;
Node() : cnt{}, len{}, fail{},s{}{next.assign(10,0);}
};
struct PAM {
static constexpr int ALPHABET_SIZE = 10;
int sz, tot, last;
vector<Node> t;
PAM() {
init();
}
void init() {
t.assign(2,Node());
sz=-1;
tot=last=1;
newnode(0);
newnode(-1);
t[0].s = '$';
t[0].fail = 1;
}
int newnode(int l) { // 建立一个新节点,长度为 l
sz++;
t[sz].len = l;
t[sz].fail = t[sz].cnt = 0;
return sz;
}
int getfail(int x) { // 找后缀回文
while (t[tot - t[x].len - 1].s != t[tot].s) x = t[x].fail;
return x;
}
void insert(char c) { // 建树
t.emplace_back();
t[++tot].s = c;
int now = getfail(last);
if (!t[now].next[c - '0']) {
int x = newnode(t[now].len + 2);
t[x].fail = t[getfail(t[now].fail)].next[c - '0'];
t[now].next[c - '0'] = x;
}
last = t[now].next[c - '0'];
t[last].cnt++;
}
void work(){
for(int i=tot;i>=2;i--){
t[t[i].fail].cnt+=t[i].cnt;
t[t[i].fail].cnt%=mo;
}
}
};
void solve(){
int n;
cin>>n;
string s;
cin>>s;
PAM pam;
for(auto x:s){
pam.insert(x);
}
vector<Node> o=pam.t;
pam.work();
vector<Node> cur=pam.t;
pam.t=o;
for(auto x:s){
pam.insert(x);
}
pam.work();
ll ans=0;
for(int i=2;i<=pam.tot;i++){
ll cnt=pam.t[i].cnt,len=pam.t[i].len;
if(len>n)
continue;
if(i<cur.size()){
cnt-=cur[i].cnt;
}
ans+=cnt*cnt%mo*len%mo;
ans%=mo;
}
cout<<ans<<endl;
}
signed main(){
ios::sync_with_stdio(0);
cout.tie(0);
cin.tie(0);
int t=1;
while(t--){
solve();
}
}
/*
贡献法
正难则反
数小状压
关系连边
拆位
广义单调性
*/
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 3600kb
input:
5 01010
output:
39
result:
ok 1 number(s): "39"
Test #2:
score: 0
Accepted
time: 0ms
memory: 3816kb
input:
8 66776677
output:
192
result:
ok 1 number(s): "192"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3600kb
input:
1 1
output:
1
result:
ok 1 number(s): "1"
Test #4:
score: 0
Accepted
time: 0ms
memory: 3576kb
input:
2 22
output:
12
result:
ok 1 number(s): "12"
Test #5:
score: 0
Accepted
time: 0ms
memory: 3820kb
input:
2 21
output:
2
result:
ok 1 number(s): "2"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3808kb
input:
3 233
output:
10
result:
ok 1 number(s): "10"
Test #7:
score: 0
Accepted
time: 0ms
memory: 3636kb
input:
3 666
output:
54
result:
ok 1 number(s): "54"
Test #8:
score: 0
Accepted
time: 144ms
memory: 348180kb
input:
1000000 3333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333...
output:
496166704
result:
ok 1 number(s): "496166704"
Test #9:
score: 0
Accepted
time: 507ms
memory: 1046288kb
input:
3000000 2222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222...
output:
890701718
result:
ok 1 number(s): "890701718"
Test #10:
score: 0
Accepted
time: 471ms
memory: 1048076kb
input:
3000000 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999...
output:
224009870
result:
ok 1 number(s): "224009870"
Test #11:
score: 0
Accepted
time: 448ms
memory: 1046768kb
input:
3000000 8989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989898989...
output:
51985943
result:
ok 1 number(s): "51985943"
Test #12:
score: -100
Memory Limit Exceeded
input:
3000000 1911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911911...
output:
355676465