Submission #1282221

#	Time	Username	Problem	Language	Result	Execution time	Memory
1282221		kurrykt	Knapsack (NOI18_knapsack)	C++20	100 / 100	157 ms	11532 KiB

knapsack

#include <bits/stdc++.h>
using namespace std;
using pii = pair <long long, long long>;
const int N = 1e6 + 20;

long long n, S, v[N], w[N], t[N];
vector <pii> col[N];

struct Data{
    long long w, v, t;
};

vector <Data> V;

long long dp[N];

void Process(){
    cin >> S >> n;
    for (int i = 1; i <= n; i++){
        cin >> v[i] >> w[i] >> t[i];
        t[i] = min(t[i] , S / w[i]);
        if (w[i] > S) continue;
        col[w[i]].push_back({v[i], t[i]});
    }
    for (int i = 1; i <= S; i++){
        sort(col[i].begin(), col[i].end(), greater<pii>());
        long long t = 0, id = 0;
        for (pii x : col[i]){
            id++;
            t += x.second;
            if (t > S) break;
        }
        id++;
        while (col[i].size() >= id) col[i].pop_back();
    }

    for (int i = 1; i <= S; i++){
        for (pii x : col[i]){
            long long val = x.first, T = x.second;
            int LG = __lg(T);
//            cout << i << " " << val << " " << T <<'\n';
            for (int k = 0; k <= LG; k++){
                if (T < (1LL << k)) break;
                V.push_back({i, val * (1LL << k), (1LL << k)});
                T -= (1LL << k);
            }
            if (T != 0) V.push_back({i, T * val, T});
        }
    }

    for (Data x : V){
        int w = x.w, v = x.v, t = x.t;
//        cout << w << " " << v << " " << t <<'\n';
        for (int j = S; j >= w * t; j--){
            dp[j] = max(dp[j], dp[j - w * t] + v);
        }
    }
    cout << dp[S];
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    #define TASK "test"
    if (fopen(TASK".inp","r")){
        freopen(TASK".inp","r",stdin);
        freopen(TASK".out","w",stdout);
    }
    Process();
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:67:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |         freopen(TASK".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:68:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   68 |         freopen(TASK".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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