Submission #899775

#	Time	Username	Problem	Language	Result	Execution time	Memory
899775		Ghetto	Knapsack (NOI18_knapsack)	C++17	73 / 100	1083 ms	147892 KiB

knapsack

#include <bits/stdc++.h>
using namespace std;
using lint = long long;
using pli = pair<lint, int>;
const int MAX_N = 1e5 + 5, MAX_S = 2000 + 5;

int s, n;
lint v[MAX_N];
int w[MAX_N], k[MAX_N];

lint dp[2][MAX_S];
unordered_map<int, deque<pli>> trans[MAX_N];

int main() {
    // freopen("knapsack.in", "r", stdin);

    cin >> s >> n;
    for (int i = 1; i <= n; i++) {
        cin >> v[i] >> w[i] >> k[i];
        k[i] = min(k[i], s);
    }

    for (int i = n; i >= 1; i--) {
        int parity = i % 2, opp_parity = (i + 1) % 2;
        for (int c = 0; c <= s; c++) {
            if (c < w[i]) {               
                trans[i][c].push_back({dp[opp_parity][c], c});
                dp[parity][c] = dp[opp_parity][c];
            } else {
                lint val = dp[opp_parity][c] - v[i] * (c / w[i]);

                while (trans[i][c % w[i]].size() && trans[i][c % w[i]].back().first <= val)
                    trans[i][c % w[i]].pop_back();
                trans[i][c % w[i]].push_back({val, c});

                while (trans[i][c % w[i]].front().second < c - k[i] * w[i])
                    trans[i][c % w[i]].pop_front();

                int new_c = trans[i][c % w[i]].front().second;
                dp[parity][c] = dp[opp_parity][new_c] + v[i] * ((c - new_c) / w[i]);
            }
            // cout << i << " " << c << ": " << dp[parity][c] << endl;
        } 
    }
    cout << dp[1][s] << '\n';
}

• Subtask 1: 12 / 12
• Subtask 2: 17 / 17
• Subtask 3: 20 / 20
• Subtask 4: 24 / 24
• Subtask 5: 0 / 27