Submission #629388

#	Time	Username	Problem	Language	Result	Execution time	Memory
629388		finn__	Knapsack (NOI18_knapsack)	C++17	12 / 100	1 ms	980 KiB

knapsack

#include <bits/stdc++.h>
using namespace std;

typedef struct item item;
struct item
{
    unsigned w;
    unsigned v;
    unsigned k;
};

bool item_cmp(item a, item b)
{
    if (a.w < b.w)
        return 1;
    else if (b.w < a.w)
        return 0;
    else
    {
        if (a.v < b.v)
            return 1;
        else
            return 0;
    }
}

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

    unsigned s, n;
    cin >> s >> n;

    vector<item> items(n);
    for (size_t i = 0; i < n; i++)
    {
        item &x = items[i];
        cin >> x.v >> x.w >> x.k;
    }

    sort(items.begin(), items.end(), item_cmp);

    vector<unsigned> cost;
    vector<unsigned> value;

    auto it = --items.end();
    for (unsigned w = s; w > 0; w--)
    {
        unsigned incl = s / w + 1;
        while (incl && it != --items.begin() && it->w == w)
        {
            cost.push_back(it->w);
            value.push_back(it->v);
            incl--;
            if (it->k > 1)
                it->k--;
            else
                it--;
        }
    }

    vector<vector<unsigned>> dp(cost.size(), vector<unsigned>(s + 1, 0));

    for (unsigned i = cost[0]; i < s + 1; i++)
        dp[0][i] = value[0];

    for (size_t i = 1; i < cost.size(); i++)
    {
        for (size_t j = 1; j < s + 1; j++)
        {
            dp[i][j] = dp[i - 1][j];
            if (j >= cost[i] && dp[i - 1][j - cost[i]] + value[i] > dp[i][j])
                dp[i][j] = dp[i - 1][j - cost[i]] + value[i];
        }
    }

    cout << dp[cost.size() - 1][s] << '\n';
}

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