Submission #926911

#	Time	Username	Problem	Language	Result	Execution time	Memory
926911		haru09	Knapsack (NOI18_knapsack)	C++17	100 / 100	50 ms	66456 KiB

knapsack

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define fi first
#define se second
#define task "code"

const int ar=2e3+5;
const ll mod=1e9+7;
int n,s;
vector<pair<int,int>> w[ar];
ll dp[ar][ar];
ll sum[ar][ar];
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    if (fopen(task".inp","r"))
    {
        freopen(task".inp","r",stdin);
        freopen(task".out","w",stdout);
    }
    cin>>s>>n;
    for (int i=1;i<=n;i++)
    {
        int v,c,k;
        cin>>v>>c>>k;
        w[c].push_back({v,k});
    }
    for (int i=1;i<=s;i++)
    {
        sort(w[i].begin(),w[i].end(),greater<pair<int,int>>());
        sum[i][0]=0;
        int j=1;
        for (auto [v,k]:w[i])
        {
            int last=j;
            while(i*j<=s && j-last<k)
            {
                sum[i][i*j]=sum[i][i*(j-1)]+v;
                j++;
            }
        }
    }
    for (int i=1;i<=s;i++)
    {
        for (int j=1;j<=s;j++) dp[i][j]=dp[i-1][j];
        for (int j=i;j<=s;j+=i)
        {
            for (int k=j;k<=s;k++)
            {
                dp[i][k]=max(dp[i][k],dp[i-1][k-j]+sum[i][j]);
            }
        }
    }
    ll ans=0;
    for (int i=1;i<=s;i++) ans=max(ans,dp[s][i]);
    cout<<ans;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:20:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   20 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:21:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 |         freopen(task".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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