#include "sequence.h"
// 赤コーダーになりたい
// お願い いいですか？
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
// Pragmas
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
// Namespaces
using namespace std;
using namespace __gnu_pbds;
// Data types
using si = short int;
using ll = long long;
using lll = __int128;
using ld = long double;
// Pairs
using pii = pair<int, int>;
using psi = pair<si, si>;
using pll = pair<ll, ll>;
using plll = pair<lll, lll>;
using pld = pair<ld, ld>;
#define fi first
#define se second
// For
#define Frue(i, n, N) for (int i = (n); i <= (N); i++)
#define Fru(i, n, N) for (int i = (n); i < (N); i++)
#define Frde(i, n, N) for (int i = (n); i >= (N); i--)
#define Frd(i, n, N) for (int i = (n); i > (N); i--)
// PBDS
template<typename Z>
using ordered_set = tree<Z, null_type, less<Z>, rb_tree_tag, tree_order_statistics_node_update>;
// Various outputs
template<typename Y, typename Z> ostream& operator<<(ostream &os, const pair<Y, Z> &p) {
return os << '(' << p.fi << ',' << p.se << ')';
}
template<typename Z> ostream& operator<<(ostream &os, const vector<Z> &v) {
os << '{'; bool _first = 1;
for (auto &i : v) {if (!_first) os << ", "; os << i; _first = 0;}
return os << '}';
}
template<typename Z, unsigned long long sz> ostream& operator<<(ostream &os, const array<Z, sz> &arr) {
os << '{'; bool _first = 1;
for (auto &i : arr) {if (!_first) os << ", "; os << i; _first = 0;}
return os << '}';
}
// Quick macro functions
#define sqr(x) ((x)*(x))
#define debug(x) cout << #x << " = " << (x) << '\n'
#define debugV(v, x) cout << #v << "[" << (x) << "] = " << (v[x]) << '\n'
#define rrebug(x) cerr << #x << " = " << (x) << '\n'
#define rrebugV(v, x) cerr << #v << "[" << (x) << "] = " << (v[x]) << '\n'
#define All(x) x.begin(), x.end()
#define Sort(x) sort(All(x))
#define Reverse(x) reverse(All(x))
#define Uniqueify(x) Sort(x); x.erase(unique(All(x)), x.end())
#define RandomSeed chrono::steady_clock::now().time_since_epoch().count()
#define MultipleTestcases int _tc; cin >> _tc; for (int _cur_tc = 1; _cur_tc <= _tc; _cur_tc++)
// Check min and max
template<typename Z> void chmin(Z &a, Z b) {a = min(a, b);}
template<typename Z> void chmax(Z &a, Z b) {a = max(a, b);}
// Modular arithmetic
template<int MOD>
class ModInt {
public:
int v;
ModInt() : v(0) {}
ModInt(long long _v) {
v = int((-MOD < _v && _v < MOD) ? (_v) : (_v % MOD));
if (v < 0) v += MOD;
}
friend bool operator==(const ModInt &a, const ModInt &b) {return a.v == b.v;}
friend bool operator!=(const ModInt &a, const ModInt &b) {return a.v != b.v;}
friend bool operator< (const ModInt &a, const ModInt &b) {return a.v < b.v;}
friend bool operator<=(const ModInt &a, const ModInt &b) {return a.v <= b.v;}
friend bool operator> (const ModInt &a, const ModInt &b) {return a.v > b.v;}
friend bool operator>=(const ModInt &a, const ModInt &b) {return a.v >= b.v;}
ModInt &operator+=(const ModInt &a) {if ((v += a.v) >= MOD) v -= MOD; return *this;}
ModInt &operator-=(const ModInt &a) {if ((v -= a.v) < 0) v += MOD; return *this;}
ModInt &operator*=(const ModInt &a) {v = 1ll * v * a.v % MOD; return *this;}
ModInt &operator/=(const ModInt &a) {return (*this) *= inverse(a);}
friend ModInt pow(ModInt a, long long x) {
ModInt res = 1;
for (; x; x /= 2, a *= a) if (x & 1) res *= a;
return res;
}
friend ModInt inverse(ModInt a) {return pow(a, MOD - 2);}
ModInt operator+ () const {return ModInt( v);}
ModInt operator- () const {return ModInt(-v);}
ModInt operator++() const {return *this += 1;}
ModInt operator--() const {return *this -= 1;}
friend ModInt operator+(ModInt a, const ModInt &b) {return a += b;}
friend ModInt operator-(ModInt a, const ModInt &b) {return a -= b;}
friend ModInt operator*(ModInt a, const ModInt &b) {return a *= b;}
friend ModInt operator/(ModInt a, const ModInt &b) {return a /= b;}
friend istream &operator>>(istream &is, ModInt &v) {return is >> v.v;}
friend ostream &operator<<(ostream &os, const ModInt &v) {return os << v.v;}
};
const int ModA = 998244353;
const int ModC = 1e9 + 7;
using MintA = ModInt<ModA>;
using MintC = ModInt<ModC>;
// Other constants
const ll INF = 1e18;
const ll iINF = 1e9;
const ld EPS = 1e-9;
const ld iEPS = 1e-6;
struct SegtreeLazy {
using Elm = pii; // {max, min}
using H_Elm = int;
Elm DEFAULT = {-iINF, iINF};
#define m ((l+r) >> 1)
#define lc (pos << 1)
#define rc (lc | 1)
int sz;
vector<Elm> seg;
vector<H_Elm> lazy;
SegtreeLazy(int sz = 1) : sz(sz) {
seg = vector<Elm>((sz << 2) + 1, DEFAULT);
lazy = vector<H_Elm>((sz << 2) + 1, 0);
}
void updateNode(int pos, int l, int r, H_Elm val) {
seg[pos] = {seg[pos].fi + val, seg[pos].se + val};
lazy[pos] += val;
}
Elm merge(Elm a, Elm b) {
return {max(a.fi, b.fi), min(a.se, b.se)};
}
void checkLazy(int pos, int l, int r) {
if (lazy[pos]) {
updateNode(lc, l, m, lazy[pos]);
updateNode(rc, m+1, r, lazy[pos]);
lazy[pos] = 0;
}
}
void build(int pos, int l, int r, vector<H_Elm> &v) {
if (l == r) {
seg[pos] = {v[l], v[l]};
return;
}
build(lc, l, m, v);
build(rc, m+1, r, v);
seg[pos] = merge(seg[lc], seg[rc]);
}
void build(vector<H_Elm> &v) {build(1, 0, sz-1, v);}
void update(int pos, int l, int r, int ul, int ur, H_Elm val) {
if (l > r || ul > ur || ul > r || l > ur) {return;}
if (ul <= l && r <= ur) {
updateNode(pos, l, r, val);
return;
}
checkLazy(pos, l, r);
update(lc, l, m, ul, ur, val);
update(rc, m+1, r, ul, ur, val);
seg[pos] = merge(seg[lc], seg[rc]);
}
void update(int ul, int ur, H_Elm val) {update(1, 0, sz-1, ul, ur, val);}
Elm query(int pos, int l, int r, int ql, int qr) {
if (l > r || ql > qr || ql > r || l > qr) {return DEFAULT;}
if (ql <= l && r <= qr) {return seg[pos];}
checkLazy(pos, l, r);
return merge(query(lc, l, m, ql, qr), query(rc, m+1, r, ql, qr));
}
Elm query(int ql, int qr) {return query(1, 0, sz-1, ql, qr);}
#undef m
#undef lc
#undef rc
};
ostream& operator<<(ostream &os, SegtreeLazy &S) {
for (int i = 0; i < S.sz; i++) os << S.query(i, i) << ' ';
return os << '\n';
}
struct FenwickTree {
using Elm = int;
int sz;
vector<Elm> BIT;
FenwickTree(int sz = 1) : sz(sz) {
BIT.assign(sz+1, 0);
}
void update(int idx, Elm val) {
idx++;
for (; idx <= sz; idx += (idx & -idx)) {BIT[idx] += val;}
}
Elm sum(int idx) {
idx++;
Elm ret = 0;
for (; idx > 0; idx -= (idx & -idx)) {ret += BIT[idx];}
return ret;
}
Elm query(int l, int r) {return sum(r) - sum(l-1);}
};
SegtreeLazy G_Pref, G_Suff, L_Pref, L_Suff;
FenwickTree Gr, Le;
bool check(int l, int r, int N, vector<int> &A, int val) {
int gr = Gr.query(l, r), le = Le.query(l, r);
int len = r - l + 1;
int eq = len - gr - le;
bool needGreater = (gr < le);
int target = abs(gr - le) - eq;
// cout << l << ' ' << r << '\n';
// cout << gr << ' ' << le << ' ' << eq << '\n';
// cout << "---\n";
// debug(needGreater);
// debug(target);
int cur = 0;
if (needGreater) {
int cl = 0, cr = 0;
if (l > 1) cl = G_Suff.query(0, l-1).fi - G_Suff.query(l, l).fi;
if (r < N-1) cr = G_Pref.query(r+1, N-1).fi - G_Pref.query(r, r).fi;
// debug(G_Suff); debug(G_Pref);
// debug(cl); debug(cr);
cur = max(cur, cl + cr);
cl = 0, cr = 0;
if (l > 1) cl = L_Suff.query(0, l-1).fi - L_Suff.query(l, l).fi;
if (r < N-1) cr = L_Pref.query(r+1, N-1).fi - L_Pref.query(r, r).fi;
cur = max(cur, cl + cr);
} else {
int cl = 0, cr = 0;
if (l > 1) cl = G_Suff.query(0, l-1).se - G_Suff.query(l, l).se;
if (r < N-1) cr = G_Pref.query(r+1, N-1).se - G_Pref.query(r, r).se;
cur = max(cur, cl + cr);
cl = 0, cr = 0;
if (l > 1) cl = L_Suff.query(0, l-1).se - L_Suff.query(l, l).se;
if (r < N-1) cr = L_Pref.query(r+1, N-1).se - L_Pref.query(r, r).se;
cur = max(cur, cl + cr);
}
// cout << '\n';
return (cur >= target);
}
int sequence(int N, std::vector<int> A) {
vector<vector<int>> occ(N+1);
for (int i = 0; i < N; i++) occ[A[i]].push_back(i);
// Greater = +1
// Less = -1
G_Pref = G_Suff = L_Pref = L_Suff = SegtreeLazy(N);
Gr = Le = FenwickTree(N);
// Initially, everything is greater
vector<int> init(N);
for (int i = 0; i < N; i++) init[i] = 2*i + 2;
G_Pref.build(init); L_Pref.build(init);
Reverse(init);
G_Suff.build(init); L_Suff.build(init);
for (int i = 0; i < N; i++) Gr.update(i, 1);
int ans = 1;
for (int i = 1; i <= N; i++) {
if (occ[i].empty()) continue;
// Turn i to less in LSkew
for (auto j : occ[i]) L_Pref.update(j, N-1, -2);
for (auto j : occ[i]) L_Suff.update(0, j, -2);
for (auto j : occ[i]) Gr.update(j, -1);
int cs = (int)occ[i].size();
for (int pl = 0, pr = -1; pl < cs; pl++) {
while (pr + 1 < cs) {
if (check(occ[i][pl], occ[i][pr+1], N, A, i)) pr++;
else break;
}
ans = max(ans, pr - pl + 1);
}
// Turn i to less in GSkew
for (auto j : occ[i]) G_Pref.update(j, N-1, -2);
for (auto j : occ[i]) G_Suff.update(0, j, -2);
for (auto j : occ[i]) Le.update(j, 1);
}
return ans;
}
#ifdef Zanite
int main() {
int N;
assert(1 == scanf("%d", &N));
std::vector<int> A(N);
for (int i = 0; i < N; ++i) {
assert(1 == scanf("%d", &A[i]));
}
int result = sequence(N, A);
printf("%d\n", result);
return 0;
}
#endif
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Incorrect |
1358 ms |
118024 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Execution timed out |
2044 ms |
131404 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
