Submission #887137

#	Time	Username	Problem	Language	Result	Execution time	Memory
887137		box	Financial Report (JOI21_financial)	C++17	100 / 100	274 ms	19420 KiB

Main

#include <bits/stdc++.h>
using namespace std;

using pii = pair<int, int>;

const int N = 3e5, N_ = 1 << 19;

int n, d, a[N];
int order[N];
int dp[N];
pii seg[N_ * 2];
int big[N_ * 2];

void bld(int k, int l, int r) {
    big[k] = 0;
    seg[k] = {-1, -1};
    if (l < r) {
        int m = (l + r) / 2;
        bld(k * 2, l, m), bld(k * 2 + 1, m + 1, r);
    }
}

pii operator+(const pii one, const pii two) {
    if (one == pii{-2, -2} || two == pii{-2, -2}) return {-2, -2};
    if (one == pii{-1, -1}) return two;
    if (two == pii{-1, -1}) return one;
    if (two.first - one.second > d) return {-2, -2};
    return {one.first, two.second};
}

void upd(int k, int l, int r, int i) {
    if (l == r) {
        big[k] = dp[i];
        seg[k] = {i, i};
    } else {
        int m = (l + r) / 2;
        i <= m ? upd(k * 2, l, m, i) : upd(k * 2 + 1, m + 1, r, i);
        big[k] = max(big[k * 2], big[k * 2 + 1]);
        seg[k] = seg[k * 2] + seg[k * 2 + 1];
    }
}

bool pos(int k, int l, int r, int ql, int qr, pii &v) {
    if (ql > r || qr < l) return 0;
    if (ql <= l && qr >= r) {
        if ((seg[k] + v) != pii{-2, -2}) {
            v = seg[k] + v;
            return 0;
        }
        if (l == r) return 1;
        int m = (l + r) / 2;
        if ((seg[k * 2 + 1] + v) != pii{-2, -2}) {
            v = seg[k * 2 + 1] + v;
            return pos(k * 2, l, m, ql, qr, v);
        }
        return pos(k * 2 + 1, m + 1, r, ql, qr, v);
    }
    int m = (l + r) / 2;
    return pos(k * 2 + 1, m + 1, r, ql, qr, v) ? 1 : pos(k * 2, l, m, ql, qr, v);
}

int qry(int k, int l, int r, int ql, int qr) {
    if (ql > r || qr < l) return 0;
    if (ql <= l && qr >= r) return big[k];
    int m = (l + r) / 2;
    return max(qry(k * 2, l, m, ql, qr), qry(k * 2 + 1, m + 1, r, ql, qr));
}

void calc_dp(int i) {
    pii v = {-1, -1};
    pos(1, 0, n - 1, 0, i, v);
    // cout << i << " => " << v.first << ' ' << v.second << endl;
    dp[i] = 1 + [&]() {
        if (v == pii{-1, -1}) return 0;
        if (i - v.second > d) return 0;
        int l = max(0, v.first - d);
        return qry(1, 0, n - 1, l, i);
    }();
    upd(1, 0, n - 1, i);
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cin >> n >> d;
    for (int i = 0; i < n; i++) cin >> a[i];
    iota(order, order + n, 0);
    sort(order, order + n, [&](int i, int j) {
        if (a[i] == a[j]) return i > j;
        return a[i] < a[j];
    });
    bld(1, 0, n - 1);
    for (int i = 0; i < n; i++) calc_dp(order[i]);
    cout << *max_element(dp, dp + n) << '\n';
}

• Subtask 1: 14 / 14
• Subtask 2: 14 / 14
• Subtask 3: 20 / 20
• Subtask 4: 12 / 12
• Subtask 5: 5 / 5
• Subtask 6: 35 / 35