Submission #638047

#	Time	Username	Problem	Language	Result	Execution time	Memory
638047		zandler	Knapsack (NOI18_knapsack)	C++14	73 / 100	8 ms	596 KiB

knapsack

#include <bits/stdc++.h>
using namespace std;
int dp[2001];
pair<pair<int,int>,int> a[2001];
vector<int> pref[2001];
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int s, n; cin >> s >> n;
    for(int i=0;i<n;i++){
        cin >> a[i].first.first >> a[i].first.second;
        cin >> a[i].second;
        
    }
    sort(a, a+n);
    for(int i=n-1;i>=0;i--){
        //cout << a[i].second << ' ';
        int v = a[i].first.second;
        for(int j=0;j<a[i].second && v*pref[v].size()<s;j++){

            int st = 0;
            if(pref[v].size()){
                st = pref[v].back();
            }
            pref[v].push_back(st);
            pref[v].back()+=a[i].first.first;
        }
    }
    // for(int i=1;i<=s;i++){
    //     cout << pref[i].size() << ' ';
    // }
    for(int i=1;i<=s;i++){
        for(int j=s;j>=0;j--){
            for(int x=pref[i].size()-1; x>=0; x--){
                if(j+(x+1)*i<= s){
                    //cout << j+x*i << '\n';
                    dp[j+(x+1)*i]=max(dp[j+(x+1)*i],dp[j]+pref[i][x]);
                }
            }
        }
    }
    cout << *max_element(dp,dp+s+1) << '\n';
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:19:54: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   19 |         for(int j=0;j<a[i].second && v*pref[v].size()<s;j++){
      |                                      ~~~~~~~~~~~~~~~~^~

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