Submission #1020198

#	Time	Username	Problem	Language	Result	Execution time	Memory
1020198		ArthuroWich	Knapsack (NOI18_knapsack)	C++17	100 / 100	81 ms	5212 KiB

knapsack

#include <bits/stdc++.h>
using namespace std;
#define int long long int
void solve() {
    int s, n;
    cin >> s >> n;
    vector<int> dp(s+1, -1);
    dp[0] = 0;
    set<int> weights;
    map<int, vector<pair<int, int>>> items;
    for (int i = 0; i < n; i++) {
        int v, w, k;
        cin >> v >> w >> k;
        weights.insert(w);
        items[w].push_back({v, k});
    }
    for (int w : weights) {
        sort(items[w].rbegin(), items[w].rend());
        int total = 0;
        for (int i = 0; i < items[w].size() && total <= 2000; i++) {
            int l;
            auto [v, k] = items[w][i]; 
            total += k*w;
            while(k > 0) {
                l = log2(k);
                if (l != 0) {
                    k -= (1<<l)-1;
                } else {
                    k--;
                    l++;
                }
                for (int x = 0; x < l; x++) {
                    if ((1LL<<x)*w > 2000) {
                        break;
                    }
                    for (int j = s; j >= 0; j--) {
                        if (j-(1LL<<x)*w < 0) {
                            break;
                        }
                        if (dp[j-(1LL<<x)*w] != -1) {
                            dp[j] = max(dp[j], dp[j-(1LL<<x)*w]+(1LL<<x)*v);
                        } 
                    }
                }
            }
        }

    }
    int ans = 0;
    for (int i : dp) {
        ans = max(ans, i);
    }
    cout << ans << endl;
}
int32_t main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int t;
    t = 1;
    while(t--) {
        solve();
    }
}

Compilation message (stderr)

knapsack.cpp: In function 'void solve()':
knapsack.cpp:20:27: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |         for (int i = 0; i < items[w].size() && total <= 2000; i++) {
      |                         ~~^~~~~~~~~~~~~~~~~

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