Submission #1083855

#	Time	Username	Problem	Language	Result	Execution time	Memory
1083855		tkvinhtruongquang	Knapsack (NOI18_knapsack)	C++14	17 / 100	1 ms	604 KiB

knapsack

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
    int S, N;
    cin >> S >> N;

    vector<vector<pair<int, int>>> items(S + 1); // items grouped by weight

    // Read input and group by weight
    for (int i = 0; i < N; i++) {
        int V, W, K;
        cin >> V >> W >> K;
        items[W].emplace_back(V, K);
    }

    vector<long long> dp(S + 1, 0);

    for (int w = 1; w <= S; w++) {
        if (!items[w].empty()) {
            // Sort by value in descending order
            sort(items[w].rbegin(), items[w].rend());

            // Process the most valuable ⌊S/w⌋ items
            int limit = S / w;
            for (int j = 0; j < min((int)items[w].size(), limit); j++) {
                int value = items[w][j].first;
                int count = items[w][j].second;
                for (int k = 1; count > 0 && k <= count; k *= 2) {
                    int use = min(k, count);
                    count -= use;
                    for (int s = S; s >= use * w; s--) {
                        dp[s] = max(dp[s], dp[s - use * w] + use * value);
                    }
                }
            }
        }
    }

    cout << dp[S] << endl;
    return 0;
}

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