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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 |
---|---|---|---|---|---|---|---|---|---|
#65953 | #2273. Suffixes may Contain Prefixes | dlg | TL | 0ms | 0kb | C++17 | 3.2kb | 2022-12-04 16:20:24 | 2022-12-04 16:20:25 |
Judging History
answer
#if not _GLIBCXX_DEBUG
#define NDEBUG 1
#endif
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define sp ' '
#define endl '\n'
#define fi first
#define se second
#define loop(i, l, r) for(int i=(int)(l); i<=(int)(r); i++)
#define rloop(i, l, r) for(int i=(int)(l); i>=(int)(r); i--)
#define all(x) (x).begin(), (x).end()
template<typename T>
ostream &operator<<(ostream &os, vector<T> a) {
os << "[";
for (auto it : a)
os << it << ",";
os << "]";
return os;
}
template<typename T, typename T2>
ostream &operator<<(ostream &os, pair<T, T2> a) {
os << "{";
os << a.fi << sp << a.se;
os << "}";
};
const int INF = numeric_limits<int>::max() / 2;
const int N = 2005;
#if _GLIBCXX_DEBUG
const int B1 = 100, B2 = 100, M1 = 1500450271, M2 = 1007050321;
#else
const int B1 = 71, B2 = 59, M1 = 1500450271, M2 = 1007050321;
#endif
int p1[N], p2[N];
void prepP() {
p1[0] = 1;
p2[0] = 1;
for (int i = 1; i < N; i++) {
p1[i] = 1LL * p1[i - 1] * B1 % M1;
p2[i] = 1LL * p2[i - 1] * B2 % M2;
}
}
class HashX {
public:
int h1[N], h2[N];
void prepHash(string s) {
h1[0] = h2[0] = 0;
for (int i = 1; i <= s.size(); i++) {
h1[i] = (1LL * h1[i - 1] * B1 + s[i - 1]) % M1;
h2[i] = (1LL * h2[i - 1] * B2 + s[i - 1]) % M2;
}
}
pair<int, int> get(int L, int R) {
L++;
int len = R - L + 1;
int ans1 = (h1[R] - 1LL * h1[L - 1] * p1[len]) % M1;
int ans2 = (h2[R] - 1LL * h2[L - 1] * p2[len]) % M2;
ans1 += (ans1 < 0 ? M1 : 0);
ans2 += (ans2 < 0 ? M2 : 0);
return {ans1, ans2};
}
} h;
string s;
int n;
int dp[N][N];
pair<int, int> state[N][26];
void prepState() {
h.prepHash(s);
std::map<std::pair<int,int>,int> prefixHashes;
for(int i=1;i<=s.size();i++){
prefixHashes[h.get(0,i)]++;
}
loop(i, 0, s.size()) {
//string str = s.substr(0, i);
for (char c = 'a'; c <= 'z'; c++) {
//str += c;
int nexti=i+1;
while(nexti!=0 and h.get(0,nexti)!=[&]{
auto targethash=h.get(i+1-nexti,i);
targethash={
(int64_t(targethash.first)*B1+c) % M1,
(int64_t(targethash.second)*B2+c) % M2,
};
return targethash;
}()) nexti--;
int cnt=0;
for(int j=0;j<=i;j++){
auto targethash=h.get(j,i);
if(j>i) assert(targethash.first==0);
targethash={
(int64_t(targethash.first)*B1+c) % M1,
(int64_t(targethash.second)*B2+c) % M2,
};
cnt+=prefixHashes[targethash];
}
//assert(i!=2);
state[i][c-'a']={nexti,cnt};
//assert(std::cerr<<i<<' '<<c<<' '<<nexti<<' '<<cnt<<'\n');
}
}
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> s >> n;
prepP();
h.prepHash(s);
//s = "!" + s;
prepState();
loop(i, 0, N - 1)
loop(j, 0, N - 1)
dp[i][j] = -INF;
dp[0][0] = 0;
loop(i, 0, n) {
loop(j, 0, s.size()) {
if (dp[i][j] == -INF)
continue;
for (char c = 'a'; c <= 'z'; c++) {
auto trans = state[j][c - 'a'];
dp[i + 1][trans.fi] = max(dp[i + 1][trans.fi], dp[i][j] + trans.se);
}
}
}
int ans = 0;
loop(i, 0, s.size())
ans = max(ans, dp[n][i]);
cout << ans << endl;
}
詳細信息
Test #1:
score: 0
Time Limit Exceeded
input:
fsfffsfffssfsfffsfsfffsfffffsfffsfffssfsfffsfsfffsffssfffsfffsfffssfsfffsfsfffsfffffsfffsfffssfsfffsfsfffsffssfffsfffsfffssfsfffsfsfffsfffffsfffsfffssfsfffsfsfffsffssfffsfffsfffssfsfffsfsfffsfffffsfffsfsfsfffsfffssfsfffsfsfffsfffffsfffsfffssfsfffsfsfffsffssfffsfffsfffssfsfffsfsfsfsfffsfffssfsfffsfsf...