Submission #937722

#	Time	Username	Problem	Language	Result	Execution time	Memory
937722		hengliao	Knapsack (NOI18_knapsack)	C++17	100 / 100	44 ms	4972 KiB

knapsack

#include<bits/stdc++.h>
using namespace std;

#define F first
#define S second
#define pb push_back
#define vll vector<ll>
#define pll pair<ll, ll>
typedef long long ll;

const ll mxN=2005;

vector<pair<ll, ll>> pos[mxN];
ll dp[mxN];

bool compare(pll a, pll b){
    return a.F>b.F;
}

void solve(){
    memset(dp, 0, sizeof(dp));
    ll n, s;
    cin>>s>>n;
    for(ll i=0;i<n;i++){
        ll v, w, k;
        cin>>v>>w>>k;
        pos[w].pb({v, k});
    }

    for(ll i=1;i<mxN;i++){
        sort(pos[i].begin(), pos[i].end(), compare);
    }

    for(ll w=1;w<=s;w++){
        ll cnt=0;
        pll lef={0, 0};
        ll mx=s/w;
        for(auto &[v, num]:pos[w]){
            if(cnt+num>mx){
                lef={v, mx-cnt};
                break;
            }
            cnt+=num;
            for(ll rep=0;rep<num;rep++){
                for(ll i=s;i>=w;i--){
                    dp[i]=max(dp[i], dp[i-w]+v);
                }
            }
        }
        if(lef.S!=0){
            ll num=lef.S;
            for(ll rep=0;rep<num;rep++){
                for(ll i=s;i>=w;i--){
                    dp[i]=max(dp[i], dp[i-w]+lef.F);
                }
            }
        }
    }

    ll ans=0;

    for(ll i=1;i<=s;i++){
        ans=max(ans, dp[i]);
    }

    cout<<ans<<'\n';
}

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

    solve();
    return 0;
}

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