제출 #573726

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
573726		eecs	Uplifting Excursion (BOI22_vault)	C++17	90 / 100	5094 ms	1748 KiB

vault

#pragma GCC optimize("Ofast,unroll-loops")
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

void chk(int &x, int y) {
    if (x < y) x = y;
}

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);
    f[lim] = 0;
    for (int i = -m; i <= m; i++) if (i) {
        vector<int> g(2 * lim + 1, -1e9);
        for (int j = -lim; j <= lim; j++) if (f[lim + j] > -1e8) {
            for (int k = 0; k <= a[i]; k++) {
                if (i > 0 && j + i * k > lim) break;
                if (i < 0 && j + i * k < -lim) break;
                if (j + i * k >= -lim && j + i * k <= lim) {
                    chk(g[lim + j + i * k], f[lim + j] + k);
                }
            }
            for (int k = 0; k <= b[i]; k++) {
                if (i < 0 && j - i * k > lim) break;
                if (i > 0 && j - i * k < -lim) break;
                if (j - i * k >= -lim && j - i * k <= lim) {
                    chk(g[lim + j - i * k], f[lim + j] - k);
                }
            }
        }
        swap(f, g);
    }
    if (f[L + lim] < -1e8) cout << "impossible\n";
    else cout << ans + f[L + lim] << "\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: 0 / 10