Submission #866591

#	Time	Username	Problem	Language	Result	Execution time	Memory
866591		12345678	Knapsack (NOI18_knapsack)	C++17	100 / 100	73 ms	3160 KiB

knapsack

#include <bits/stdc++.h>

using namespace std;

const int nx=2e3+5;
int s, n, v, w, k, dp[2][nx], mx, cnt[nx];
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq[nx];

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>s>>n;
    for (int i=0; i<n; i++)
    {
        cin>>v>>w>>k;
        pq[w].push({v, k});
        cnt[w]+=k;
        if (cnt[w]-pq[w].top().second>s/w) cnt[w]-=pq[w].top().second, pq[w].pop();
    }
    vector<pair<int, int>> d;
    for (int i=1; i<=s; i++)
    {
        int tmp=s/i;
        stack<pair<int, int>> s;
        while (!pq[i].empty()) s.push(pq[i].top()), pq[i].pop();
        while (tmp>0&&!s.empty())
        {
            tmp--;
            auto [x, y]=s.top();
            s.pop();
            d.push_back({i, x});
            if (--y!=0) s.push({x, y});
        }
    }
    for (int i=0; i<d.size(); i++)
    {
        int c=i%2, p=1-c;
        v=d[i].second; w=d[i].first;
        //cout<<v<<' '<<w<<'\n';
        for (int j=1; j<=s; j++)
        {
            dp[c][j]=dp[p][j];
            if (j>=w) dp[c][j]=max(dp[c][j], dp[p][j-w]+v);
            mx=max(mx, dp[c][j]);
        }
    }
    cout<<mx;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:35:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |     for (int i=0; i<d.size(); i++)
      |                   ~^~~~~~~~~

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