Submission #865770

#	Time	Username	Problem	Language	Result	Execution time	Memory
865770		thundereyex	Knapsack (NOI18_knapsack)	C++14	0 / 100	1 ms	604 KiB

knapsack

#include<bits/stdc++.h>
using namespace std;
#define all(x) x.begin(), x.end()
int main(){
    long long int n,k;
    cin>>n>>k;
    int max2=0;
    vector<vector<long long int>>v1;
    vector<long long int>v2;
       for(int i=0;i<k;i++){
        long long  int a,b,c;
         cin>>a>>b>>c;
         if(b<=n){
          long long   int g= n/b;
              // for(int j=0;j<min(g,c);j++){
                   v2.push_back(a);
                   v2.push_back(b);
                   v2.push_back(min(g,c));
                   v1.push_back(v2);
                   v2.clear();
                   int f=min(g,c);
                   max2=max({max2,f});
              // }
 
        
         }
         
        //  v2.clear();
    }
      vector<long long int>dp(n+1,0);
    // sort(v1.begin(),v1.end(),greater<vector<int>>());
    if(n<=100&&max2<=10){
    long long int max1=0;
      for (int i = 1; i <= v1.size(); i++) 
      for (int j = n; j >= v1[i-1][1]; j--)
        for (int t = 0; t <= v1[i-1][2]; t++)
          if (j >= v1[i-1][1] * t) {
            dp[j] = max(dp[j], dp[j - v1[i-1][1] * t] + v1[i-1][0] * t);
          }
        

    cout<<dp[n]<<endl;
}
else if (1 <= n && n <= 1e5 && max2 <= 1e9) {
 
    /*
      Observation: The numbers of taken product must less than S since 1 <= Wi <= S -> maximum taken product: S / W[i]
      -> consider the top valued S/W[i] items for each W[i]
    */
    vector<pair<int,int>> obj[n];
    long long dp[2001];
    memset(dp, 0, sizeof dp);
    for (int i = 1; i <= v1.size(); i++) {
      obj[v1[i][1]].push_back({v1[i][0],v1[i][2]});
    }
 
    for (int i = 0; i <= n; i++) {
      if (obj[i].size() == 0) continue;
      sort(all(obj[i]), greater<pair<int, int>>());
 
      int id = 0;
      for (int j = 0; j  <=n; j++) {
        if (id >= obj[i].size()) break;
        for (int k = n; k >= i; k--) {
          dp[k] = max(dp[k], dp[k - i] + obj[i][id].first);
        }
        --obj[i][id].second;
        if (obj[i][id].second == 0) ++id;
      }
    }
    cout << dp[n] << endl;
  } 
}
// #include<bits/stdc++.h>
// using namespace std;
// int main(){
//       vector<pair<int,int>> arr[2];
//       arr[1].push_back({100,3});
//       arr[1].push_back({50,4});
//       cout<<arr[1].size()<<endl;
  
// }

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:34:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |       for (int i = 1; i <= v1.size(); i++)
      |                       ~~^~~~~~~~~~~~
knapsack.cpp:33:19: warning: unused variable 'max1' [-Wunused-variable]
   33 |     long long int max1=0;
      |                   ^~~~
knapsack.cpp:53:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   53 |     for (int i = 1; i <= v1.size(); i++) {
      |                     ~~^~~~~~~~~~~~
knapsack.cpp:63:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |         if (id >= obj[i].size()) break;
      |             ~~~^~~~~~~~~~~~~~~~

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