Submission #404514

#	Time	Username	Problem	Language	Result	Execution time	Memory
404514		CrouchingDragon	Knapsack (NOI18_knapsack)	C++17	100 / 100	73 ms	2776 KiB

knapsack

#include "bits/stdc++.h"

using namespace std;

#define endl '\n'
#define debug(x) cerr << #x << " == " << (x) << '\n';
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)

using ll = long long;

const int INF = 0x3f3f3f3f;
const ll LINF = 0x3f3f3f3f3f3f3f3fLL;

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    ll S;
    int N;
    cin >> S >> N;

    vector<vector<array<ll, 2>>> items(S + 1);

    for (int i = 0; i < N; ++i) {
        ll V, W, K;
        cin >> V >> W >> K;
        items[W].push_back({V, K});
    }

    vector<ll> dp(S + 1, 0);

    auto insert = [&](ll V, ll W) {
        for (ll x = S - W; x >= 0; --x) {
            dp[x + W] = max(dp[x + W], dp[x] + V);
        }
    };

    for (ll W = 1; W <= S; ++W) {
        sort(rall(items[W]));
        ll left = S / W;
        for (auto [V, K] : items[W]) {
            if (left == 0) break;
            K = min(K, left);
            left -= K;
            for (int x = 1; x <= K; K -= x, x *= 2) insert(x * V, x * W);
            if (K > 0) insert(K * V, K * W);
        }
    }

    ll ans = *max_element(all(dp));
    cout << ans << endl;

    exit(0);
}

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