Submission #975900

#	Time	Username	Problem	Language	Result	Execution time	Memory
975900		gaga999	Sequence (APIO23_sequence)	C++17	31 / 100	2053 ms	59476 KiB

sequence

// #pragma GCC optimize("Ofast,no-stack-protector")
// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx,avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
#define lowbit(x) ((x) & -(x))
#define ml(a, b) ((1ll * (a) * (b)) % M)
#define tml(a, b) (a) = ((1ll * (a) * (b)) % M)
#define ad(a, b) ((0ll + (a) + (b)) % M)
#define tad(a, b) (a) = ((0ll + (a) + (b)) % M)
#define mi(a, b) ((0ll + M + (a) - (b)) % M)
#define tmi(a, b) (a) = ((0ll + M + (a) - (b)) % M)
#define tmin(a, b) (a) = min((a), (b))
#define tmax(a, b) (a) = max((a), (b))
#define iter(a) (a).begin(), (a).end()
#define riter(a) (a).rbegin(), (a).rend()
#define init(a, b) memset((a), (b), sizeof(a))
#define cpy(a, b) memcpy((a), (b), sizeof(a))
#define uni(a) a.resize(unique(iter(a)) - a.begin())
#define size(x) (int)x.size()
#define pb emplace_back
#define mpr make_pair
#define ls(i) ((i) << 1)
#define rs(i) ((i) << 1 | 1)
#define INF 0x3f3f3f3f
#define NIF 0xc0c0c0c0
#define eps 1e-9
#define F first
#define S second
#define AC cin.tie(0)->sync_with_stdio(0)
using namespace std;
typedef long long llt;
typedef __int128_t lll;
typedef pair<int, int> pii;
typedef pair<double, double> pdd;
typedef pair<llt, llt> pll;
typedef pair<llt, int> pli;
typedef complex<double> cd;
// const int M = 998244353;

// random_device rm;
// mt19937 rg(rm());
// default_random_engine rg(rm());
// uniform_int_distribution<int> rd(INT_MIN, INT_MAX);
// uniform_real_distribution<double> rd(0, M_PI);

void db() { cerr << "\n"; }
template <class T, class... U>
void db(T a, U... b) { cerr << a << " ", db(b...); }

inline char gc()
{
    const static int SZ = 1 << 16;
    static char buf[SZ], *p1, *p2;
    if (p1 == p2 && (p2 = buf + fread(p1 = buf, 1, SZ, stdin), p1 == p2))
        return -1;
    return *p1++;
}
void rd() {}
template <typename T, typename... U>
void rd(T &x, U &...y)
{
    x = 0;
    bool f = 0;
    char c = gc();
    while (!isdigit(c))
        f ^= !(c ^ 45), c = gc();
    while (isdigit(c))
        x = (x << 1) + (x << 3) + (c ^ 48), c = gc();
    f && (x = -x), rd(y...);
}

template <typename T>
void prt(T x)
{
    if (x < 0)
        putchar('-'), x = -x;
    if (x > 9)
        prt(x / 10);
    putchar((x % 10) ^ 48);
}

const int N = 5e5 + 5;
int n, ar[N];
vector<int> pl[N];

struct TR
{
    int lx, ln, rx, rn, sum;
    TR operator+(const TR &rh) const
    {
        TR cr;
        cr.sum = sum + rh.sum;
        cr.lx = max(lx, sum + rh.lx);
        cr.ln = min(ln, sum + rh.ln);
        cr.rx = max(rh.rx, rh.sum + rx);
        cr.rn = min(rh.rn, rh.sum + rn);
        return cr;
    }
    inline void ini(int v)
    {
        lx = max(0, v), rx = max(0, v);
        ln = min(0, v), rn = min(0, v);
        sum = v;
    }
} tr[N << 2], vv;
int ql, qr, qv;

#define L l, m, ls(id)
#define R m + 1, r, rs(id)
#define pul() tr[id] = tr[ls(id)] + tr[rs(id)]
void blt(int l, int r, int id)
{
    if (l == r)
    {
        tr[id].ini(1);
        return;
    }
    int m = (l + r) >> 1;
    blt(L), blt(R), pul();
}

void qy(int l, int r, int id)
{
    if (ql <= l && r <= qr)
    {
        vv = vv + tr[id];
        return;
    }
    int m = (l + r) >> 1;
    if (ql <= m)
        qy(L);
    if (qr > m)
        qy(R);
}

void cg(int l, int r, int id)
{
    if (ql <= l && r <= qr)
    {
        tr[id].ini(qv);
        return;
    }
    int m = (l + r) >> 1;
    if (ql <= m)
        cg(L);
    if (qr > m)
        cg(R);
    pul();
}

bool ck(int lm)
{
    blt(1, n, 1);
    for (int i = 1; i <= n; i++)
    {
        if (size(pl[i]) >= lm)
        {
            for (int p : pl[i])
                ql = qr = p, qv = 0, cg(1, n, 1);
            for (int j = lm - 1; j < size(pl[i]); j++)
            {
                int l = pl[i][j - lm + 1], r = pl[i][j];
                vv.ini(0), ql = l, qr = r, qy(1, n, 1);
                int cv = vv.sum;
                if (abs(cv) <= lm)
                    return 1;
                vv.ini(0), ql = 1, qr = l, qy(1, n, 1);
                if (cv < 0)
                {
                    if (-cv - lm <= vv.rx)
                        return 1;
                    cv += vv.rx;
                }
                else
                {
                    if (cv - lm <= -vv.rn)
                        return 1;
                    cv += vv.rn;
                }
                vv.ini(0), ql = r, qr = n, qy(1, n, 1);
                if (cv < 0)
                {
                    if (-cv - lm <= vv.lx)
                        return 1;
                    cv += vv.lx;
                }
                else
                {
                    if (cv - lm <= -vv.ln)
                        return 1;
                    cv += vv.ln;
                }
            }
        }
        for (int p : pl[i])
            ql = qr = p, qv = -1, cg(1, n, 1);
    }
    return 0;
}

int sequence(int _n, vector<int> aa)
{
    n = _n;
    for (int i = 1; i <= n; i++)
        pl[ar[i] = aa[i - 1]].pb(i);
    int l = 1, r = 1;
    for (int i = 1; i <= n; i++)
        tmax(r, size(pl[i]));
    while (l < r)
    {
        int m = (l + r + 1) >> 1;
        if (ck(m))
            l = m;
        else
            r = m - 1;
    }
    return l;
}

// signed main()
// {
//     int nn;
//     rd(nn);
//     vector<int> aa(nn);
//     for (int i = 0; i < nn; i++)
//         rd(aa[i]);
//     prt(sequence(nn, aa)), putchar('\n');
// }

• Subtask 1: 11 / 11
• Subtask 2: 0 / 17
• Subtask 3: 7 / 7
• Subtask 4: 0 / 12
• Subtask 5: 13 / 13
• Subtask 6: 0 / 22
• Subtask 7: 0 / 18