Submission #919747

#	Time	Username	Problem	Language	Result	Execution time	Memory
919747		imarn	Knapsack (NOI18_knapsack)	C++14	100 / 100	240 ms	8016 KiB

knapsack

#include<bits/stdc++.h>
#pragma GCC optimize("Ofast,unroll-loops")
#define ll long long
#define pii pair<int,int>
#define pll pair<ll,ll>
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(),x.end()
#define vi vector<int>
#define vvi vector<vi>
#define vp vector<pii>
using namespace std;
const int N=1e6+5;
ll dp[2][2005]{0};
ll ans[2005]{0};
deque<pll>dq[2005];
vector<pll>g[2005];
int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);
    int s,n;cin>>s>>n;
    ll a[n],b[n],c[n];
    for(int i=0;i<n;i++)cin>>a[i]>>b[i]>>c[i],g[b[i]].pb({a[i],c[i]});
    int cr=0;
    for(int i=1;i<=s;i++){
        sort(g[i].begin(),g[i].end(),greater<pll>());
        int t = s/i;int tt=0;
        for(auto it : g[i]){
            tt+=it.s;
            a[cr]=it.f,b[cr]=i,c[cr]=it.s;cr++;
            if(tt>=t)break;
        }
    }n=cr;
    int nw=0,pr=0;
    for(int i=0;i<n;i++){
        pr=nw;nw=1-nw;
        for(int j=b[i];j<=s;j++){int id=(j)/b[i];
            dp[nw][j]=dp[pr][j];
            while(!dq[j%b[i]].empty()&&dq[j%b[i]].back().f+min(id-dq[j%b[i]].back().s+1,c[i])*a[i]<=dp[pr][j-b[i]]+a[i])dq[j%b[i]].pop_back();
            while(!dq[j%b[i]].empty()&&id-dq[j%b[i]].front().s+1>=c[i]){
                ans[j%b[i]]=max(ans[j%b[i]],dq[j%b[i]].front().f+c[i]*a[i]);dq[j%b[i]].pop_front();
            }
            dq[j%b[i]].pb({dp[pr][j-b[i]],id});
            if(!dq[j%b[i]].empty())dp[nw][j]=max(dp[nw][j],dq[j%b[i]].front().f+min(id-dq[j%b[i]].front().s+1,c[i])*a[i]);
            dp[nw][j]=max(dp[nw][j],ans[j%b[i]]);
        }
        for(int j=0;j<b[i];j++)dq[j].clear(),ans[j]=0;
    }cout<<dp[nw][s];
}

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