Submission #760327

#	Time	Username	Problem	Language	Result	Execution time	Memory
760327		sofija6	Knapsack (NOI18_knapsack)	C++14	100 / 100	36 ms	2880 KiB

knapsack

#include <bits/stdc++.h>
#define ll long long
#define MAXN 100010
#define MAXS 2010
using namespace std;
vector<pair<ll,ll> > items[MAXS];
vector<pair<ll,ll> > cur;
ll dp[MAXS][2];
int main()
{
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    ll s,n,v,w,k,ans=0;
    cin >> s >> n;
    for (ll i=1;i<=n;i++)
    {
        cin >> v >> w >> k;
        items[w].push_back({v,k});
    }
    for (ll i=1;i<=s;i++)
    {
        if (items[i].empty())
            continue;
        sort(items[i].begin(),items[i].end(),greater<pair<ll,ll> >());
        cur.clear();
        ll sum=0,pos=0;
        for (ll j=0;(j+1)*i<=s;j++)
        {
            if (!items[i][pos].second)
                pos++;
            if (pos==items[i].size())
                break;
            items[i][pos].second--;
            sum+=items[i][pos].first;
            cur.push_back({(j+1)*i,sum});
        }
        for (auto j : cur)
        {
            w=j.first;
            v=j.second;
            for (ll l=0;l+w<=s;l++)
                dp[l+w][1]=max(dp[l+w][1],dp[l][0]+v);
        }
        for (ll j=0;j<=s;j++)
            dp[j][0]=dp[j][1];
    }
    for (ll i=1;i<=s;i++)
        ans=max(ans,dp[i][0]);
    cout << ans;
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:30:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |             if (pos==items[i].size())
      |                 ~~~^~~~~~~~~~~~~~~~~

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