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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 |
---|---|---|---|---|---|---|---|---|---|
#658081 | #7876. Cyclic Substrings | H_ZzZ | WA | 3ms | 21984kb | C++20 | 3.1kb | 2024-10-19 16:07:16 | 2024-10-19 16:07:22 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#define int long long
const int mod = 998244353;
constexpr int MAXN = 6e6+ 50;
int nnn;
namespace pam {
int sz, tot, last;
int cnt[MAXN], ch[MAXN][10], len[MAXN], fail[MAXN];
char s[MAXN];
int node(int l) { // 建立一个新节点,长度为 l
sz++;
memset(ch[sz], 0, sizeof(ch[sz]));
len[sz] = l;
fail[sz] = cnt[sz] = 0;
return sz;
}
void clear() { // 初始化
sz = -1;
last = 0;
s[tot = 0] = '$';
node(0);
node(-1);
fail[0] = 1;
}
int getfail(int x) { // 找后缀回文
while (s[tot - len[x] - 1] != s[tot]) x = fail[x];
return x;
}
void insert(char c) { // 建树
s[++tot] = c;
int now = getfail(last);
if (!ch[now][c - '0']) {
int x = node(len[now] + 2);
fail[x] = ch[getfail(fail[now])][c - '0'];
ch[now][c - '0'] = x;
}
last = ch[now][c - '0'];
cnt[last]++;
}
void solve() {
long long ans = 0;
for (int i = sz; i >= 0; i--) {
cnt[fail[i]] += cnt[i];
}
}
} // namespace pam
namespace pam2 {
int sz, tot, last;
int cnt[MAXN], ch[MAXN][10], len[MAXN], fail[MAXN];
char s[MAXN];
int node(int l) { // 建立一个新节点,长度为 l
sz++;
memset(ch[sz], 0, sizeof(ch[sz]));
len[sz] = l;
fail[sz] = cnt[sz] = 0;
return sz;
}
void clear() { // 初始化
sz = -1;
last = 0;
s[tot = 0] = '$';
node(0);
node(-1);
fail[0] = 1;
}
int getfail(int x) { // 找后缀回文
while (s[tot - len[x] - 1] != s[tot]) x = fail[x];
return x;
}
void insert(char c) { // 建树
s[++tot] = c;
int now = getfail(last);
if (!ch[now][c - '0']) {
int x = node(len[now] + 2);
fail[x] = ch[getfail(fail[now])][c - '0'];
ch[now][c - '0'] = x;
}
last = ch[now][c - '0'];
cnt[last]++;
}
void ssolve()
{
for (int i = sz; i >= 0; i--) {
cnt[fail[i]] += cnt[i];
}
}
long long solve() {
long long ans = 0;
for (int i = 2; i <= sz; i++) { // 更新答案
if(len[i] > nnn) break;
ans += ((len[i])%mod * (cnt[i]* cnt[i])%mod)%mod;
ans %= mod;
}
return ans%mod;
}
}
string s;
signed main() {
ios::sync_with_stdio(0);
cin.tie(0), cout.tie(0);
cin >> nnn;
cin >> s;
string ss = s + s;
pam::clear();
pam2::clear();
for (char i : s) {
pam::insert(i);
}
for(char s : ss)
{
pam2::insert(s);
}
pam2::ssolve();
pam::solve();
for(int i = 2 ;i <= pam::sz; ++ i)
{
pam2::cnt[i] -= pam::cnt[i];
}
cout << pam2::solve() << '\n';
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 21964kb
input:
5 01010
output:
39
result:
ok 1 number(s): "39"
Test #2:
score: -100
Wrong Answer
time: 3ms
memory: 21984kb
input:
8 66776677
output:
160
result:
wrong answer 1st numbers differ - expected: '192', found: '160'