Submission #491332

#	Time	Username	Problem	Language	Result	Execution time	Memory
491332		DDTerziev04	Knapsack (NOI18_knapsack)	C++14	100 / 100	71 ms	3696 KiB

knapsack

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

const int MAXN=1e5, MAXS=2000;

long long dp[MAXS+1];
vector<pair<int, int> > v[MAXS+1];

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int s, n;
    cin >> s >> n;

    for(int i=0; i<n; i++)
    {
        int p, w, h;
        cin >> p >> w >> h;

        v[w].push_back({p, h});
    }

    for(int i=1; i<=s; i++)
    {
        sort(v[i].begin(), v[i].end());
        reverse(v[i].begin(), v[i].end());

        dp[i]=-1;
    }
    dp[0]=0;

    long long ans=0;
    for(int i=1; i<=s; i++)
    {
        if(v[i].size()==0)
        {
            continue;
        }

        for(int j=s; j>=0; j--)
        {
            int idx=0, p=0, h=v[i][0].second;
            for(int u=1; u*i<=j; u++)
            {
                if(u>h)
                {
                    idx++;

                    if(idx>=v[i].size())
                    {
                        break;
                    }

                    h+=v[i][idx].second;
                }
                p+=v[i][idx].first;

                if(dp[j-u*i]==-1)
                {
                    continue;
                }

                dp[j]=max(dp[j], dp[j-u*i]+p);
            }

            ans=max(ans, dp[j]);
        }
    }

    cout << ans << "\n";

    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:53:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   53 |                     if(idx>=v[i].size())
      |                        ~~~^~~~~~~~~~~~~

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