Submission #1180634

#	Time	Username	Problem	Language	Result	Execution time	Memory
1180634		souvenir_vayne	Knapsack (NOI18_knapsack)	C++20	73 / 100	463 ms	327680 KiB

knapsack

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <chrono>
#define pb push_back
#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define endl '\n'
#define ll long long
#define f first
#define fin cin
#define fout cout
#define s second
#define FAST cin.tie(0), cout.tie(0), ios::sync_with_stdio(0)
#define debug(x) cerr << "DEBUG " << x << endl
#define debug2(x, y) cerr << "DEBUG " << x << " " << y << endl
#define debug3(x, y, z) cerr << "DEBUG " << x << " " << y << " " << z << endl
#define debug4(x, y, z, o) cerr << "DEBUG " << x << " " << y << " " << z << " " << o << endl
#define all(x) x.begin(), x.end()
#define left esquerda
#define lb lower_bound
#define right direita
using namespace std;
void setIO(string s) {
    ios_base::sync_with_stdio(0); cin.tie(0);
    freopen((s+".in").c_str(),"r",stdin);
    freopen((s+".out").c_str(),"w",stdout);
}
typedef pair<int, int> pii;
typedef vector<vector<char>> mat;
typedef pair<int, string> pis;
const ll mod = 1e9 + 7, MAXN = 2e5 + 5;
typedef vector<int> vi;
typedef pair<int, pair<int, int>> piii;

int dp[2][2005], ans = 0;
vector<pii> ri;
vector<int> items[2001];

void solve() {
    int n, s;
    cin >> s >> n;
    for(int i = 0; i < n; i++) {
        int v, w, k;
        cin >> v >> w >> k;
        k = min(k, s/w);

        for(int j = 0; j < k; j++)
            items[w].push_back(v);
    }

    for(int i = 1; i < 2001; i++) {
        sort(all(items[i]), greater<int>());
        for(int j = 0; j < min((int)items[i].size(), s/i); j++)
            ri.push_back({items[i][j], i});
    } 
   

    for(int i = 0; i < ri.size(); i++) {
        for(int j = s; j >= 0; j--) {
            if(!i && j >= ri[i].s)
                dp[i][j] = ri[i].f;
            
            else if(i) {
                dp[i & 1][j] = dp[!(i & 1)][j];
                if(j >= ri[i].s)
                    dp[i & 1][j] = max(dp[i & 1][j], dp[!(i & 1)][j - ri[i].s] + ri[i].f);
            }
            ans = max(ans, dp[i & 1][j]);
        }
    }
    cout << ans << endl;
}

int32_t main() {
    int ct = 1;
    while(ct--)
        solve();
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'void setIO(std::string)':
knapsack.cpp:25:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   25 |     freopen((s+".in").c_str(),"r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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+".out").c_str(),"w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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