Submission #941264

#	Time	Username	Problem	Language	Result	Execution time	Memory
941264		LOLOLO	Sequence (APIO23_sequence)	C++17	0 / 100	2050 ms	69240 KiB

sequence

#include <bits/stdc++.h>
using namespace std;
typedef  long long ll;
 
#define           f     first
#define           s     second
#define           pb    push_back
#define           ep    emplace
#define           eb    emplace_back
#define           lb    lower_bound
#define           ub    upper_bound
#define       all(x)    x.begin(), x.end()
#define      rall(x)    x.rbegin(), x.rend()
#define   uniquev(v)    sort(all(v)), (v).resize(unique(all(v)) - (v).begin())
#define     mem(f,x)    memset(f , x , sizeof(f))
#define        sz(x)    (int)(x).size()
#define  __lcm(a, b)    (1ll * ((a) / __gcd((a), (b))) * (b))
#define          mxx    *max_element
#define          mnn    *min_element
#define    cntbit(x)    __builtin_popcountll(x)
#define       len(x)    (int)(x.length())
 
const int N = 5e5 + 100;
const int M = 2e6;
 
struct ST{
    vector <pair <int, int>> seg;
    vector <int> laz;
    ST(int n) {
        for (int i = 0; i <= 4 * n + 10; i++) {
            seg.pb({0, 0});
            laz.pb(0);
        }
    }
 
    void push(int id) {
        int &t = laz[id];
        laz[id * 2] += t;
        laz[id * 2 + 1] += t;
        seg[id * 2].f += t, seg[id * 2].s += t;
        seg[id * 2 + 1].f += t, seg[id * 2 + 1].s += t;
        t = 0;
    }
 
    pair <int, int> merge(pair <int, int> A, pair <int, int> B) {
        pair <int, int> C;
        C.f = min(A.f, B.f);
        C.s = max(A.s, B.s);
        return C;
    }
 
    void upd(int id, int l, int r, int u, int v, int lz) {
        if (l > v || r < u)
            return;
 
        if (l >= u && r <= v) {
            laz[id] += lz;
            seg[id].f += lz;
            seg[id].s += lz;
            return;
        }
 
        push(id);
        int m = (l + r) / 2;
        upd(id * 2, l, m, u, v, lz);
        upd(id * 2 + 1, m + 1, r, u, v, lz);
        seg[id] = merge(seg[id * 2], seg[id * 2 + 1]);
    }
 
    pair <int, int> get(int id, int l, int r, int u, int v) {
        if (l >= u && r <= v)
            return seg[id];
 
        push(id);
        int m = (l + r) / 2;
        if (m + 1 <= u) {
            return get(id * 2 + 1, m + 1, r, u, v);
        }
 
        if (m >= v) {
            return get(id * 2, l, m, u, v);
        }
 
        return merge(get(id * 2, l, m, u, v), get(id * 2 + 1, m + 1, r, u, v));
    }
};
 
vector <int> pos[N];
int a[N], n;
bool is(int l1, int r1, int l, int r) {
    return max(l1, l) <= min(r1, r);
} 

bool intersect(pair <int, int> A, pair <int, int> B, int d) {
    int l = A.f, r = A.s, l1 = B.f, r1 = B.s, a = 0;
    if (l1 - d >= l && l1 - d <= r)
        a |= is(l1 - d * 2, l1 - d, l, r);

    if (r1 - d >= l && r1 - d <= r)
        a |= is(r1 - d * 2, r1 - d, l, r);
 
    if (l + d >= l1 && l + d <= r1)
        a |= is(l + d, l1 + d * 2, l1, r1);
 
    if (r + d >= l1 && r + d <= r1)
        a |= is(r + d, r + d * 2, l1, r1);
 
    return a;
}
 
bool check(int m) {
    ST seg(n);
    for (int i = 1; i <= n; i++) {
        seg.upd(1, 0, n, i, n, 1);
    }
 
    for (int i = 1; i <= n; i++) {
        for (int j = 0; j < sz(pos[i]); j++) {
            if (j >= m - 1) {
                if (intersect(seg.get(1, 0, n, 0, pos[i][j - m + 1] - 1), seg.get(1, 0, n, pos[i][j], n), m * 2)) {
                    return 1;
                }
            } 
        }
 
        for (int j = 0; j < sz(pos[i]); j++) {
            seg.upd(1, 0, n, pos[i][j], n, -2);
        }
    }
 
    return 0;
}
 
int sequence(int N, vector <int> A) {
    n = N;
    for (int i = 1; i <= n; i++)
        pos[i].clear();
 
    for (int i = 1; i <= n; i++) {
        a[i] = A[i - 1];
        pos[a[i]].pb(i);
    }
 
    int l = 0, r = n, m, ans = 0;
    while (l <= r) {
        m = (l + r) / 2;
        if (check(m)) {
            ans = m;
            l = m + 1;
        } else {
            r = m - 1;
        }
    }
 
    return ans;
}
 
/*int main() {
    cout << sequence(14, {2, 6, 2, 5, 3, 4, 2, 1, 4, 3, 5, 6, 3, 2}) << '\n';
    cout << sequence(9, {1, 1, 2, 3, 4, 3, 2, 1, 1}) << '\n';
    cout << sequence(14, {2, 6, 2, 5, 3, 4, 2, 1, 4, 3, 5, 6, 3, 2}) << '\n';
    return 0;
}*/

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