Submission #548563

#	Time	Username	Problem	Language	Result	Execution time	Memory
548563		Alexandruabcde	Knapsack (NOI18_knapsack)	C++14	12 / 100	1 ms	212 KiB

knapsack

#include <bits/stdc++.h>

using namespace std;

constexpr int NMAX = 1e5 + 5;
constexpr int SUMMAX = 2005;
typedef long long LL;

struct Item {
    int value;
    int weight;
    int copies;

    bool operator < (const Item &other) const {
        return (weight < other.weight || (weight == other.weight && value < other.value));
    }
};

int S, N;

Item V[NMAX];
LL dp[SUMMAX];

int main () {
    cin >> S >> N;

    for (int i = 1; i <= N; ++ i )
        cin >> V[i].value >> V[i].weight >> V[i].copies;

    sort(V+1, V+N+1);

    for (int i = 1; i <= S; ++ i )
        dp[i] = -1;

    for (int i = 1; i <= N; ++ i ) {
        LL cnt = 0;
        int dr = i;

        while (dr <= N && V[dr].weight == V[i].weight) {
            cnt += 1LL * V[dr].copies;
            ++ dr;
        }

        int ind = i;
        int w = V[i].weight;
        for (int nr = 1; ind < dr && 1LL * nr <= cnt && nr <= S / w; ++ nr ) {
            for (int s = S; s >= w; -- s ) {
                if (dp[s - w] != -1)
                    dp[s] = max(dp[s], dp[s - w] + 1LL * V[ind].value);
            }

            -- V[ind].copies;
            if (V[ind].copies == 0)
                ++ ind;
        }

        i = dr - 1;
    }

    LL ans = 0;
    for (int i = 0; i <= S; ++ i )
        ans = max(ans, dp[i]);
    cout << ans << '\n';

    return 0;
}

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