Submission #881520

#	Time	Username	Problem	Language	Result	Execution time	Memory
881520		andro	Knapsack (NOI18_knapsack)	C++14	100 / 100	65 ms	5728 KiB

knapsack

#include <bits/stdc++.h>
#define int long long
using namespace std;
signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n,s;
    cin>>s>>n;
    int v[n+1];
    int w[n+1];
    int k[n+1];
    for(int i=1;i<=n;i++)cin>>v[i]>>w[i]>>k[i];
    vector<pair<int,int>>A[s+1];
    for(int i=1;i<=n;i++)A[w[i]].push_back({v[i],k[i]});
    vector<pair<int,int>>u;
    for(int i=1;i<=s;i++){
        int mx=s/i;
        sort(A[i].begin(),A[i].end());
        reverse(A[i].begin(),A[i].end());
        for(auto it:A[i]){
            if(mx<0)break;
            for(int j=1;j<=it.second;j++){
                if(mx<0)break;
                u.push_back({it.first,i});
                mx--;
            }
        }
    }
    /*
    int dp[u.size()][s+1];
    for(int i=0;i<u.size();i++)for(int j=0;j<=s;j++)dp[i][j]=0;
    dp[0][u[0].second]=u[0].first;
    for(int i=1;i<u.size();i++){
        for(int j=0;j<=s;j++)dp[i][j]=dp[i-1][j];
        for(int j=u[i].second;j<=s;j++)dp[i][j]=max(dp[i][j],dp[i-1][j-u[i].second]+u[i].first);
    }
    int ans=0;
    for(int i=1;i<=s;i++)ans=max(ans,dp[u.size()-1][i]);
    cout<<ans;*/
    vector<int>dp(s+1,0);
    vector<int>new_dp(s+1,0);
    new_dp[u[0].second]=u[0].first;
    for(int i=1;i<u.size();i++){
        for(int j=0;j<=s;j++)dp[j]=new_dp[j];
        for(int j=u[i].second;j<=s;j++)dp[j]=max(dp[j],new_dp[j-u[i].second]+u[i].first);
        swap(dp,new_dp);
    }
    int ans=0;
    for(int i=1;i<=s;i++)ans=max(ans,new_dp[i]);
    cout<<ans;
}
/*
dobijas v[i]
*/

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:43:18: 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]
   43 |     for(int i=1;i<u.size();i++){
      |                 ~^~~~~~~~~

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