Submission #1008415

#	Time	Username	Problem	Language	Result	Execution time	Memory
1008415		cpdreamer	Knapsack (NOI18_knapsack)	C++17	100 / 100	52 ms	3752 KiB

knapsack

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <utility>
using namespace __gnu_pbds;
using namespace std;

typedef tree<int,null_type,less<int>,rb_tree_tag,
        tree_order_statistics_node_update> indexed_set;
const int max_n=INT_MAX;
const int inf=1e8;
typedef long long  ll;
#define LLM LONG_LONG_MAX
#define pb push_back
#define F first
#define P pair
#define all(v) v.begin(),v.end()
#define V vector
#define S second
const long long MOD = 998244353; // 1e9 + 7

void file(){
    freopen("input.txt.txt","r",stdin);
    freopen("output.txt.txt","w",stdout);
}
void setio(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}
struct product{
    int value;
    int weight;
    int copies;
};
bool sorted(product a,product b){
    return a.value>b.value;
}
void solve() {
    int n,W;
    cin>>W>>n;
    V<V<int>>weights(W+1);
    product A[n];
    for(int i=0;i<n;i++){
        cin>>A[i].value>>A[i].weight>>A[i].copies;
    }
    sort(A,A+n,sorted);
    for(int i=0;i<n;i++){
        int a=A[i].value,b=A[i].weight,c=A[i].copies;
        int limit=(W/b)-(int)weights[b].size();
        for(int j=0;j<min(limit,c);j++){
            weights[b].pb(a);
        }
    }
    ll dp[W+1];
    memset(dp,0LL,sizeof(dp));
    for(int i=1;i<=W;i++){
        for(auto u:weights[i]){
            for(int j=W;j>=i;j--){
                dp[j]=max(dp[j],dp[j-i]+u);
            }
        }
    }
    cout<<*max_element(dp,dp+W+1)<<endl;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    //file();
    solve();
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'void file()':
knapsack.cpp:22:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   22 |     freopen("input.txt.txt","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:23:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |     freopen("output.txt.txt","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp: In function 'void setio(std::string)':
knapsack.cpp:26:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:27:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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