結果
| 問題 | No.284 門松と魔法(2) |
| ユーザー |
 maspy
|
| 提出日時 | 2022-04-25 04:11:23 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 399 ms / 5,000 ms |
| コード長 | 18,205 bytes |
| コンパイル時間 | 2,639 ms |
| コンパイル使用メモリ | 223,748 KB |
| 最終ジャッジ日時 | 2025-01-28 21:32:44 |
|
ジャッジサーバーID （参考情報） |
judge5 / judge4 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| other | AC * 40 |
ソースコード
#line 1 "/home/maspy/compro/library/my_template.hpp"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pi = pair<ll, ll>;
using vi = vector<ll>;
using u32 = unsigned int;
using u64 = unsigned long long;
using i128 = __int128;
template <class T>
using vc = vector<T>;
template <class T>
using vvc = vector<vc<T>>;
template <class T>
using vvvc = vector<vvc<T>>;
template <class T>
using vvvvc = vector<vvvc<T>>;
template <class T>
using vvvvvc = vector<vvvvc<T>>;
template <class T>
using pq = priority_queue<T>;
template <class T>
using pqg = priority_queue<T, vector<T>, greater<T>>;
#define vec(type, name, ...) vector<type> name(__VA_ARGS__)
#define vv(type, name, h, ...) \
vector<vector<type>> name(h, vector<type>(__VA_ARGS__))
#define vvv(type, name, h, w, ...) \
vector<vector<vector<type>>> name( \
h, vector<vector<type>>(w, vector<type>(__VA_ARGS__)))
#define vvvv(type, name, a, b, c, ...) \
vector<vector<vector<vector<type>>>> name( \
a, vector<vector<vector<type>>>( \
b, vector<vector<type>>(c, vector<type>(__VA_ARGS__))))
#define FOR_(n) for (ll _ = 0; (_) < (ll)(n); ++(_))
#define FOR(i, n) for (ll i = 0; (i) < (ll)(n); ++(i))
#define FOR3(i, m, n) for (ll i = (m); (i) < (ll)(n); ++(i))
#define FOR_R(i, n) for (ll i = (ll)(n)-1; (i) >= 0; --(i))
#define FOR3_R(i, m, n) for (ll i = (ll)(n)-1; (i) >= (ll)(m); --(i))
#define FOR_subset(t, s) for (ll t = s; t >= 0; t = (t == 0 ? -1 : (t - 1) & s))
#define all(x) x.begin(), x.end()
#define len(x) ll(x.size())
#define elif else if
#define eb emplace_back
#define mp make_pair
#define mt make_tuple
#define fi first
#define se second
#define stoi stoll
template <typename T>
T SUM(vector<T> &A) {
T sum = T(0);
for (auto &&a: A) sum += a;
return sum;
}
#define MIN(v) *min_element(all(v))
#define MAX(v) *max_element(all(v))
#define LB(c, x) distance((c).begin(), lower_bound(all(c), (x)))
#define UB(c, x) distance((c).begin(), upper_bound(all(c), (x)))
#define UNIQUE(x) sort(all(x)), x.erase(unique(all(x)), x.end())
int popcnt(int x) { return __builtin_popcount(x); }
int popcnt(u32 x) { return __builtin_popcount(x); }
int popcnt(ll x) { return __builtin_popcountll(x); }
int popcnt(u64 x) { return __builtin_popcountll(x); }
// (0, 1, 2, 3, 4) -> (-1, 0, 1, 1, 2)
int topbit(int x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); }
int topbit(u32 x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); }
int topbit(ll x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); }
int topbit(u64 x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); }
// (0, 1, 2, 3, 4) -> (-1, 0, 1, 0, 2)
int lowbit(int x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); }
int lowbit(u32 x) { return (x == 0 ? -1 : 31 - __builtin_clz(x)); }
int lowbit(ll x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); }
int lowbit(u64 x) { return (x == 0 ? -1 : 63 - __builtin_clzll(x)); }
template <typename T, typename U>
T ceil(T x, U y) {
return (x > 0 ? (x + y - 1) / y : x / y);
}
template <typename T, typename U>
T floor(T x, U y) {
return (x > 0 ? x / y : (x - y + 1) / y);
}
template <typename T, typename U>
pair<T, T> divmod(T x, U y) {
T q = floor(x, y);
return {q, x - q * y};
}
ll binary_search(function<bool(ll)> check, ll ok, ll ng) {
assert(check(ok));
while (abs(ok - ng) > 1) {
auto x = (ng + ok) / 2;
if (check(x))
ok = x;
else
ng = x;
}
return ok;
}
template <class T, class S>
inline bool chmax(T &a, const S &b) {
return (a < b ? a = b, 1 : 0);
}
template <class T, class S>
inline bool chmin(T &a, const S &b) {
return (a > b ? a = b, 1 : 0);
}
vi s_to_vi(const string& S, char first_char) {
vi A(S.size());
FOR(i, S.size()) { A[i] = S[i] - first_char; }
return A;
}
template <typename T>
vector<T> cumsum(vector<T> &A, int off = 1) {
int N = A.size();
vector<T> B(N + 1);
FOR(i, N) { B[i + 1] = B[i] + A[i]; }
if (off == 0) B.erase(B.begin());
return B;
}
template <typename CNT, typename T>
vc<CNT> bincount(const vc<T> &A, int size) {
vc<CNT> C(size);
for (auto &&x: A) { ++C[x]; }
return C;
}
template <typename T>
vector<int> argsort(const vector<T> &A) {
// stable
vector<int> ids(A.size());
iota(all(ids), 0);
sort(all(ids),
[&](int i, int j) { return A[i] < A[j] || (A[i] == A[j] && i < j); });
return ids;
}
// A[I[0]], A[I[1]], ...
template <typename T>
vc<T> rearrange(const vc<T> &A, const vc<int> &I) {
int n = len(A);
assert(len(I) == n);
vc<T> B(n);
FOR(i, n) B[i] = A[I[i]];
return B;
}
#line 1 "/home/maspy/compro/library/other/io.hpp"
// based on yosupo's fastio
#include <unistd.h>
namespace detail {
template <typename T, decltype(&T::is_modint) = &T::is_modint>
std::true_type check_value(int);
template <typename T>
std::false_type check_value(long);
} // namespace detail
template <typename T>
struct is_modint : decltype(detail::check_value<T>(0)) {};
template <typename T>
using is_modint_t = enable_if_t<is_modint<T>::value>;
template <typename T>
using is_not_modint_t = enable_if_t<!is_modint<T>::value>;
struct Scanner {
FILE *fp;
char line[(1 << 15) + 1];
size_t st = 0, ed = 0;
void reread() {
memmove(line, line + st, ed - st);
ed -= st;
st = 0;
ed += fread(line + ed, 1, (1 << 15) - ed, fp);
line[ed] = '\0';
}
bool succ() {
while (true) {
if (st == ed) {
reread();
if (st == ed) return false;
}
while (st != ed && isspace(line[st])) st++;
if (st != ed) break;
}
if (ed - st <= 50) {
bool sep = false;
for (size_t i = st; i < ed; i++) {
if (isspace(line[i])) {
sep = true;
break;
}
}
if (!sep) reread();
}
return true;
}
template <class T, enable_if_t<is_same<T, string>::value, int> = 0>
bool read_single(T &ref) {
if (!succ()) return false;
while (true) {
size_t sz = 0;
while (st + sz < ed && !isspace(line[st + sz])) sz++;
ref.append(line + st, sz);
st += sz;
if (!sz || st != ed) break;
reread();
}
return true;
}
template <class T, enable_if_t<is_integral<T>::value, int> = 0>
bool read_single(T &ref) {
if (!succ()) return false;
bool neg = false;
if (line[st] == '-') {
neg = true;
st++;
}
ref = T(0);
while (isdigit(line[st])) { ref = 10 * ref + (line[st++] & 0xf); }
if (neg) ref = -ref;
return true;
}
template <class T, is_modint_t<T> * = nullptr>
bool read_single(T &ref) {
long long val = 0;
bool f = read_single(val);
ref = T(val);
return f;
}
bool read_single(double &ref) {
string s;
if (!read_single(s)) return false;
ref = std::stod(s);
return true;
}
bool read_single(char &ref) {
string s;
if (!read_single(s) || s.size() != 1) return false;
ref = s[0];
return true;
}
template <class T>
bool read_single(vector<T> &ref) {
for (auto &d: ref) {
if (!read_single(d)) return false;
}
return true;
}
template <class T, class U>
bool read_single(pair<T, U> &p) {
return (read_single(p.first) && read_single(p.second));
}
template <class A, class B, class C>
bool read_single(tuple<A, B, C> &p) {
return (read_single(get<0>(p)) && read_single(get<1>(p))
&& read_single(get<2>(p)));
}
template <class A, class B, class C, class D>
bool read_single(tuple<A, B, C, D> &p) {
return (read_single(get<0>(p)) && read_single(get<1>(p))
&& read_single(get<2>(p)) && read_single(get<3>(p)));
}
void read() {}
template <class H, class... T>
void read(H &h, T &... t) {
bool f = read_single(h);
assert(f);
read(t...);
}
Scanner(FILE *fp) : fp(fp) {}
};
struct Printer {
Printer(FILE *_fp) : fp(_fp) {}
~Printer() { flush(); }
static constexpr size_t SIZE = 1 << 15;
FILE *fp;
char line[SIZE], small[50];
size_t pos = 0;
void flush() {
fwrite(line, 1, pos, fp);
pos = 0;
}
void write(const char &val) {
if (pos == SIZE) flush();
line[pos++] = val;
}
template <class T, enable_if_t<is_integral<T>::value, int> = 0>
void write(T val) {
if (pos > (1 << 15) - 50) flush();
if (val == 0) {
write('0');
return;
}
if (val < 0) {
write('-');
val = -val; // todo min
}
size_t len = 0;
while (val) {
small[len++] = char(0x30 | (val % 10));
val /= 10;
}
for (size_t i = 0; i < len; i++) { line[pos + i] = small[len - 1 - i]; }
pos += len;
}
void write(const string &s) {
for (char c: s) write(c);
}
void write(const char *s) {
size_t len = strlen(s);
for (size_t i = 0; i < len; i++) write(s[i]);
}
void write(const double &x) {
ostringstream oss;
oss << setprecision(15) << x;
string s = oss.str();
write(s);
}
void write(const long double &x) {
ostringstream oss;
oss << setprecision(15) << x;
string s = oss.str();
write(s);
}
template <class T, is_modint_t<T> * = nullptr>
void write(T &ref) {
write(ref.val);
}
template <class T>
void write(const vector<T> &val) {
auto n = val.size();
for (size_t i = 0; i < n; i++) {
if (i) write(' ');
write(val[i]);
}
}
template <class T, class U>
void write(const pair<T, U> &val) {
write(val.first);
write(' ');
write(val.second);
}
template <class A, class B, class C>
void write(const tuple<A, B, C> &val) {
auto &[a, b, c] = val;
write(a), write(' '), write(b), write(' '), write(c);
}
template <class A, class B, class C, class D>
void write(const tuple<A, B, C, D> &val) {
auto &[a, b, c, d] = val;
write(a), write(' '), write(b), write(' '), write(c), write(' '), write(d);
}
template <class A, class B, class C, class D, class E>
void write(const tuple<A, B, C, D, E> &val) {
auto &[a, b, c, d, e] = val;
write(a), write(' '), write(b), write(' '), write(c), write(' '), write(d), write(' '), write(e);
}
template <class A, class B, class C, class D, class E, class F>
void write(const tuple<A, B, C, D, E, F> &val) {
auto &[a, b, c, d, e, f] = val;
write(a), write(' '), write(b), write(' '), write(c), write(' '), write(d), write(' '), write(e), write(' '), write(f);
}
template <class T, size_t S>
void write(const array<T, S> &val) {
auto n = val.size();
for (size_t i = 0; i < n; i++) {
if (i) write(' ');
write(val[i]);
}
}
void write(i128 val) {
string s;
bool negative = 0;
if(val < 0){
negative = 1;
val = -val;
}
while (val) {
s += '0' + int(val % 10);
val /= 10;
}
if(negative) s += "-";
reverse(all(s));
if (len(s) == 0) s = "0";
write(s);
}
};
Scanner scanner = Scanner(stdin);
Printer printer = Printer(stdout);
void flush() { printer.flush(); }
void print() { printer.write('\n'); }
template <class Head, class... Tail>
void print(Head &&head, Tail &&... tail) {
printer.write(head);
if (sizeof...(Tail)) printer.write(' ');
print(forward<Tail>(tail)...);
}
void read() {}
template <class Head, class... Tail>
void read(Head &head, Tail &... tail) {
scanner.read(head);
read(tail...);
}
#define INT(...) \
int __VA_ARGS__; \
read(__VA_ARGS__)
#define LL(...) \
ll __VA_ARGS__; \
read(__VA_ARGS__)
#define STR(...) \
string __VA_ARGS__; \
read(__VA_ARGS__)
#define CHAR(...) \
char __VA_ARGS__; \
read(__VA_ARGS__)
#define DBL(...) \
double __VA_ARGS__; \
read(__VA_ARGS__)
#define VEC(type, name, size) \
vector<type> name(size); \
read(name)
#define VV(type, name, h, w) \
vector<vector<type>> name(h, vector<type>(w)); \
read(name)
void YES(bool t = 1) { print(t ? "YES" : "NO"); }
void NO(bool t = 1) { YES(!t); }
void Yes(bool t = 1) { print(t ? "Yes" : "No"); }
void No(bool t = 1) { Yes(!t); }
void yes(bool t = 1) { print(t ? "yes" : "no"); }
void no(bool t = 1) { yes(!t); }
#line 2 "/home/maspy/compro/library/ds/segtree.hpp"
template <class Monoid>
struct SegTree {
using X = typename Monoid::value_type;
using value_type = X;
vc<X> dat;
int n, log, size;
SegTree() : SegTree(0) {}
SegTree(int n) : SegTree(vc<X>(n, Monoid::unit())) {}
SegTree(vc<X> v) : n(len(v)) {
log = 1;
while ((1 << log) < n) ++log;
size = 1 << log;
dat.assign(size << 1, Monoid::unit());
FOR(i, n) dat[size + i] = v[i];
FOR3_R(i, 1, size) update(i);
}
X operator[](int i) { return dat[size + i]; }
void update(int i) { dat[i] = Monoid::op(dat[2 * i], dat[2 * i + 1]); }
void set(int i, X x) {
assert(i < n);
dat[i += size] = x;
while (i >>= 1) update(i);
}
X prod(int L, int R) {
assert(L <= R);
assert(R <= n);
X vl = Monoid::unit(), vr = Monoid::unit();
L += size, R += size;
while (L < R) {
if (L & 1) vl = Monoid::op(vl, dat[L++]);
if (R & 1) vr = Monoid::op(dat[--R], vr);
L >>= 1, R >>= 1;
}
return Monoid::op(vl, vr);
}
X prod_all() { return dat[1]; }
template <class F>
int max_right(F &check, int L) {
assert(0 <= L && L <= n && check(Monoid::unit()));
if (L == n) return n;
L += size;
X sm = Monoid::unit();
do {
while (L % 2 == 0) L >>= 1;
if (!check(Monoid::op(sm, dat[L]))) {
while (L < size) {
L = 2 * L;
if (check(Monoid::op(sm, dat[L]))) {
sm = Monoid::op(sm, dat[L]);
L++;
}
}
return L - size;
}
sm = Monoid::op(sm, dat[L]);
L++;
} while ((L & -L) != L);
return n;
}
template <class F>
int min_left(F &check, int R) {
assert(0 <= R && R <= n && check(Monoid::unit()));
if (R == 0) return 0;
R += size;
X sm = Monoid::unit();
do {
--R;
while (R > 1 && (R % 2)) R >>= 1;
if (!check(Monoid::op(dat[R], sm))) {
while (R < size) {
R = 2 * R + 1;
if (check(Monoid::op(dat[R], sm))) {
sm = Monoid::op(dat[R], sm);
R--;
}
}
return R + 1 - size;
}
sm = Monoid::op(dat[R], sm);
} while ((R & -R) != R);
return 0;
}
// モノイドが可換なら、prod_{l<=i<r}A[i^x] が計算可能
// https://codeforces.com/contest/1401/problem/F
X Xor_prod(int l, int r, int xor_val) {
assert(Monoid::commute);
X x = Monoid::unit();
FOR(k, log + 1) {
if (l >= r) break;
if (l & 1) { x = Monoid::op(x, dat[(size >> k) + ((l++) ^ xor_val)]); }
if (r & 1) { x = Monoid::op(x, dat[(size >> k) + ((--r) ^ xor_val)]); }
l /= 2, r /= 2, xor_val /= 2;
}
return x;
}
void debug() { print("segtree", dat); }
};
#line 2 "/home/maspy/compro/library/alg/monoid_max_idx.hpp"
template <typename T, T INF>
struct Monoid_Max_Idx {
using value_type = pair<T, int>;
using X = value_type;
static X op(X x, X y) { return max(x, y); }
static constexpr X unit() { return {-INF, -1}; }
static constexpr bool commute = true;
};
#line 5 "main.cpp"
// (dp val, 1個前, 2個前) を 2 個持つ。
// 同じ「2個前」は 1 つまでしか持たないようにする。
struct Mono {
using value_type = tuple<ll, ll, ll, ll, ll, ll>;
using X = value_type;
static X _add(X x, ll dp3, ll a3, ll b3) {
auto [dp1, a1, b1, dp2, a2, b2] = x;
if (b1 == b3 && dp1 < dp3) { return {dp3, a3, b3, dp2, a2, b2}; }
if (b2 == b3 && dp2 < dp3) { return {dp1, a1, b1, dp3, a3, b3}; }
if (b1 == b3 || b2 == b3) return x;
if (dp1 < dp2) { swap(dp1, dp2), swap(a1, a2), swap(b1, b2); }
if (dp2 < dp3) return {dp1, a1, b1, dp3, a3, b3};
return x;
}
static X add(X x, ll dp3, ll a3, ll b3) {
x = _add(x, dp3, a3, b3);
auto& [dp1, a1, b1, dp2, a2, b2] = x;
if (dp1 < dp2) { swap(dp1, dp2), swap(a1, a2), swap(b1, b2); }
return x;
}
static X op(X x, X y) {
if (get<0>(x) == -1) return y;
if (get<0>(y) == -1) return x;
auto [a, b, c, d, e, f] = y;
x = add(x, a, b, c);
x = add(x, d, e, f);
return x;
}
static constexpr X unit() { return {-1, -1, -1, -1, -1, -1}; }
static constexpr bool commute = true;
};
void solve() {
LL(N);
VEC(ll, A, N);
auto key = A;
UNIQUE(key);
for (auto&& a: A) a = LB(key, a) + 5;
using X = Mono::X;
N = len(key) + 10;
SegTree<Mono> seg_hi(N), seg_lo(N);
for (auto&& a: A) {
{
X x = seg_lo[a];
x = Mono::add(x, 1, a, a + 1);
x = Mono::add(x, 1, a, a + 2);
auto upd = [&](ll l, ll r) -> void {
if (l >= r) return;
auto [dp3, a3, b3, dp4, a4, b4] = seg_hi.prod(l, r);
if (b3 != a) x = Mono::add(x, dp3 + 1, a, a3);
if (b4 != a) x = Mono::add(x, dp4 + 1, a, a4);
};
auto [dp1, a1, b1, dp2, a2, b2] = seg_hi.prod(a + 1, N);
upd(a + 1, N);
if (a1 > a2) swap(a1, a2);
chmax(a1, a + 1);
chmax(a2, a + 1);
upd(a + 1, a1);
upd(a1, a1 + 1);
upd(a1 + 1, a2);
upd(a2, a2 + 1);
upd(a2 + 1, N);
seg_lo.set(a, x);
}
{
X x = seg_hi[a];
x = Mono::add(x, 1, a, a - 1);
x = Mono::add(x, 1, a, a - 2);
auto upd = [&](ll l, ll r) -> void {
if (l >= r) return;
auto [dp3, a3, b3, dp4, a4, b4] = seg_lo.prod(l, r);
if (b3 != a) x = Mono::add(x, dp3 + 1, a, a3);
if (b4 != a) x = Mono::add(x, dp4 + 1, a, a4);
};
auto [dp1, a1, b1, dp2, a2, b2] = seg_lo.prod(0, a);
upd(0, a);
if (a1 > a2) swap(a1, a2);
chmin(a1, a - 1);
chmin(a2, a - 1);
upd(0, a1);
upd(a1, a1 + 1);
upd(a1 + 1, a2);
upd(a2, a2 + 1);
upd(a2 + 1, a);
seg_hi.set(a, x);
}
}
ll ANS = 0;
{
auto [dp1, a1, b1, dp2, a2, b2] = seg_lo.prod_all();
chmax(ANS, dp1);
chmax(ANS, dp2);
}
{
auto [dp1, a1, b1, dp2, a2, b2] = seg_hi.prod_all();
chmax(ANS, dp1);
chmax(ANS, dp2);
}
if (ANS <= 2) ANS = 0;
print(ANS);
}
signed main() {
cin.tie(nullptr);
ios::sync_with_stdio(false);
cout << setprecision(15);
ll T = 1;
// LL(T);
FOR(_, T) solve();
return 0;
}