Submission #721670

#	Time	Username	Problem	Language	Result	Execution time	Memory
721670		dxz05	Uplifting Excursion (BOI22_vault)	C++17	20 / 100	2666 ms	4424 KiB

vault

#pragma GCC optimize("Ofast,O3,unroll-loops")

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
#define all(x) (x).begin(), (x).end()
#define MP make_pair
const int N = 100500;

const int LIM = 100 * 100 * 101 / 2 + 1;

vector<int> knapsack(vector<int> a){
    vector<int> dp(LIM, -1e9);
    dp[0] = 0;

    for (int x : a) {
        for (int i = LIM - 1; i >= x; i--) {
            dp[i] = max(dp[i], dp[i - x] + 1);
        }
    }

    return dp;
}

void solve(){
    int m; ll L;
    cin >> m >> L;

    if (L >= LIM || L <= -LIM){
        cout << "impossible" << endl;
        return;
    }

    vector<int> pos, neg;
    for (int i = -m; i <= m; i++){
        int x;
        cin >> x;
        while (x--){
            if (i >= 0){
                pos.push_back(i);
            } else {
                neg.push_back(-i);
            }
        }
    }

    vector<int> dp1 = knapsack(pos);
    vector<int> dp2 = knapsack(neg);

    if (L < 0){
        L = -L;
        swap(dp1, dp2);
    }

    int ans = -1e9;
    for (int x = L; x < LIM; x++) {
        int y = x - L;
        ans = max(ans, dp1[x] + dp2[y]);
    }

    if (ans < 0) {
        cout << "impossible" << endl;
    } else {
        cout << ans << endl;
    }
}

int main() {
    ios_base::sync_with_stdio(false);

#ifdef LOCAL
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif

    solve();

    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3-1: 0 / 10
• Subtask 3-2: 0 / 10
• Subtask 4-1: 0 / 10
• Subtask 4-2: 0 / 10
• Subtask 5-1: 0 / 10
• Subtask 5-2: 0 / 10
• Subtask 6-1: 0 / 10
• Subtask 6-2: 0 / 10