제출 #573795

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
573795		eecs	Uplifting Excursion (BOI22_vault)	C++17	100 / 100	1120 ms	1712 KiB

vault

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

typedef long long ll;

int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    int m;
    ll L, all = 0;
    cin >> m >> L;
    vector<ll> _a(2 * m + 1), _b(2 * m + 1);
    auto a = _a.data() + m, b = _b.data() + m;
    for (int i = -m; i <= m; i++) {
        cin >> a[i], all += max(0, i) * a[i];
    }
    if (L < 0) {
        L *= -1, all = 0;
        for (int i = 1; i <= m; i++) {
            swap(a[i], a[-i]), all += i * a[i];
        }
    }
    if (all < L) cout << "impossible\n", exit(0);
    ll ans = a[0];
    for (int i = -1; i >= -m; i--) {
        b[i] = min(a[i], (all - L) / -i);
        ans += b[i], L -= b[i] * i, a[i] -= b[i];
    }
    for (int i = 1; i <= m; i++) {
        b[i] = min(a[i], L / i);
        ans += b[i], L -= b[i] * i, a[i] -= b[i];
    }
    int lim = m * L;
    vector<int> _f(2 * lim + 1, -1e9);
    auto f = _f.data() + lim;
    f[0] = 0;
    for (int i = -m; i <= m; i++) if (i) {
        auto _g = _f;
        auto g = _g.data() + lim;
        auto tr = [&](int x) {
            if (i * x > 0) {
                for (int j = lim - i * x; j >= -lim; j--) {
                    if (g[j + i * x] < g[j] + x) g[j + i * x] = g[j] + x;
                }
            } else {
                for (int j = -lim - i * x; j <= lim; j++) {
                    if (g[j + i * x] < g[j] + x) g[j + i * x] = g[j] + x;
                }
            }
        };
        a[i] = min(a[i], 2LL * lim / abs(i));
        for (int x = 1; x <= a[i]; x <<= 1) tr(x), a[i] -= x;
        if (a[i]) tr(a[i]);
        swap(_f, _g), swap(f, g);
        b[i] = min(b[i], 2LL * lim / abs(i));
        for (int x = 1; x <= b[i]; x <<= 1) tr(-x), b[i] -= x;
        if (b[i]) tr(-b[i]);
        for (int j = -lim; j <= lim; j++) {
            f[j] = max(f[j], g[j]);
        }
    }
    if (f[L] < -1e8) cout << "impossible\n";
    else cout << ans + f[L] << "\n";
    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3-1: 10 / 10
• Subtask 3-2: 10 / 10
• Subtask 4-1: 10 / 10
• Subtask 4-2: 10 / 10
• Subtask 5-1: 10 / 10
• Subtask 5-2: 10 / 10
• Subtask 6-1: 10 / 10
• Subtask 6-2: 10 / 10