Submission #1330943

#	Time	Username	Problem	Language	Result	Execution time	Memory
1330943		Thanhs	Knapsack (NOI18_knapsack)	C++20	100 / 100	38 ms	2916 KiB

knapsack

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

#define name "TENBAI"
#define fi first
#define se second
#define int long long
#define endl '\n'
#define setmin(x, y) x = min((x), (y))
#define setmax(x, y) x = max((x), (y))
#define sqr(x) ((x) * (x))
#define all(x) x.begin(), x.end()

mt19937 hdp(chrono::high_resolution_clock::now().time_since_epoch().count());
int rand(int l, int r){return l + ((hdp() % (r - l + 1)) + r - l + 1) % (r - l + 1);}

const int SM = 2000 + 5;
const int inf = 1e18;

int n, s, f[SM];
vector<pair<int, int>> v[SM];

void solve()
{
    cin >> s >> n;
    for (int i = 1; i <= n; i++)
    {
        int va, w, k;
        cin >> va >> w >> k;
        v[w].push_back({va, k});
    }
    f[0] = 0;
    for (int i = 1; i <= s; i++)
    {
        f[i] = -inf;
        sort(all(v[i]));
    }
    for (int i = 1; i <= s; i++)
    {
        int c = 0;
        while (v[i].size() && c < s / i)
        {
            c++;
            int t = v[i].back().fi;
            for (int j = s; j >= i; j--)
                setmax(f[j], f[j - i] + t);
            v[i].back().se--;
            if (!v[i].back().se)
                v[i].pop_back();
        }
    }
    cout << *max_element(f, f + 1 + s);
}

signed main()
{
    if (fopen("in.txt", "r")) 
    {
        freopen("in.txt", "r", stdin);
        freopen("out.txt", "w", stdout);
    }
    else if (fopen(name".inp", "r"))
    {
        freopen(name".inp", "r", stdin);
        freopen(name".out", "w", stdout);
    }
    ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
    int tc = 1; 
    // cin >> tc;
    while (tc--)
        solve();
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:59:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |         freopen("in.txt", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:60:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |         freopen("out.txt", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:64:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |         freopen(name".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:65:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |         freopen(name".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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