Submission #1257883

#	Time	Username	Problem	Language	Result	Execution time	Memory
1257883		dobri_oke	Knapsack (NOI18_knapsack)	C++20	73 / 100	475 ms	327680 KiB

knapsack

//#pragma GCC target ("avx2")   
//#pragma GCC optimize ("Ofast")   
#include <bits/stdc++.h>   
using namespace std;  
//#define int long long  
#define F first 
#define S second 
#define pb push_back 
const int N = 1e6+100;
const int mod=1e9+7;
int inf=INT_MAX;
vector < pair < int, int > > g[2100];
//int lcm(int a, int b) { return a / (__gcd(a, b)) * b; }
//int binpow(int a,int b){if(!b)return 1; if(b&1)return a*binpow(a,b-1)%mod; int x=binpow(a,b/2); return x*x%mod;}
signed main(){   
    ios_base::sync_with_stdio(0);   cin.tie(0);   cout.tie(0);
    int s, n;
    cin >> s >> n;
    int c[n+1], w[n+1], k[n+1], dp[s+5]{};
    vector < pair < int, int > > a;
    for(int i=1;i<=n;i++){
        cin >> c[i] >> w[i] >> k[i];
        if(w[i]<=s) g[w[i]].pb({c[i], k[i]});
    }
    for(int i=1;i<=2000;i++){ 
        sort(g[i].begin(), g[i].end());
        reverse(g[i].begin(), g[i].end());   
    }
    for(int i=1;i<=2000;i++){
        int t=2000/i;
        for(auto [v, col] : g[i]){
            if(t>col){
                while(col--){
                    a.pb({i, v});
                }
            }
            else{
                while(t--){
                    a.pb({i, v});
                }
                break;
            }
        }
    }
    for(int i=1;i<=s;i++) dp[i]=-inf;
    for(int i=0;i<a.size();i++){
        for(int j=s-a[i].F;j>=0;j--){
            dp[j+a[i].F]=max(dp[j+a[i].F], dp[j]+a[i].S);
        }
    }
    int ans=-inf;
    for(int i=0;i<=s;i++) ans=max(ans, dp[i]);
    cout << ans;
}

• Subtask 1: 12 / 12
• Subtask 2: 17 / 17
• Subtask 3: 20 / 20
• Subtask 4: 24 / 24
• Subtask 5: 0 / 27