Submission #543795

#	Time	Username	Problem	Language	Result	Execution time	Memory
543795		zammy	Knapsack (NOI18_knapsack)	C++17	100 / 100	107 ms	38720 KiB

knapsack

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

const int inf = INT_MAX, mod = 1e9 + 7, MAX_N = (1e5), MAX_S = 2000;

void solve()
{
    int S, N;
    cin >> S >> N;
    vector<int> V(N + 1), W(N + 1), K(N + 1);
    map<int, vector<pair<int, int>>> mp;
    for (int i = 1; i <= N; i++)
    {
        cin >> V[i] >> W[i] >> K[i];
        mp[W[i]].push_back({V[i], K[i]});
    }
    int i = 1;
    vector<vector<int>> dp((int)mp.size() + 1LL, vector<int>(S + 1, -1));
    for (int i = 0; i <= S; i++)
        dp[0][i] = 0;
    for (auto &[wt, items] : mp)
    {
        sort(items.rbegin(), items.rend());
        for (int j = 0; j <= S; j++)
        {
            dp[i][j] = dp[i - 1][j];
            int curr_item = 0, cnt = 0, curr_item_cnt = 0, profit = 0;
            while (curr_item < (int)items.size() && j - ((cnt + 1) * wt) >= 0 && dp[i - 1][j - ((cnt + 1) * wt)] != -1)
            {
                cnt++;
                profit += items[curr_item].first;
                dp[i][j] = max(dp[i][j], dp[i - 1][j - (cnt * wt)] + profit);
                if (curr_item_cnt + 1 == items[curr_item].second)
                    curr_item++, curr_item_cnt = 0;
                else
                    curr_item_cnt++;
            }
        }
        i++;
    }
    cout << *max_element(dp.back().begin(), dp.back().end()) << "\n";
}

int32_t main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout << fixed;
    cout << setprecision(9);
    int tt = 1;
    // cin >> tt;
    for (int i = 1; i <= tt; i++)
    {
        // cout << "Case #" << i << ": ";
        solve();
    }
    cerr << "time taken : " << (float)clock() / CLOCKS_PER_SEC << " secs" << endl;
}

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