Submission #1106582

#	Time	Username	Problem	Language	Result	Execution time	Memory
1106582		vjudge1	Knapsack (NOI18_knapsack)	C++17	100 / 100	43 ms	3656 KiB

knapsack

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

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int W, N;
    cin >> W >> N;
    vector<vector<pair<int, int>>> g(W + 1);
    vector<int> dp(W + 1);
    for (int i = 0; i < N; i++) {
        int v, w, k;
        cin >> v >> w >> k;
        if (w > W) continue;
        g[w].push_back({ -v,k });
    }
    for (int i = 1; i <= W; i++) {
        if (g[i].empty()) continue;
        sort(g[i].begin(), g[i].end());
    }
    for (int w = 1; w <= W; w++) {
        if (g[w].empty()) continue;
        int j = 0;
        for (int i = 1; i <= W / w; i++) {
            auto&& [v, k] = g[w][j];
            for (int x = W; x - w >= 0; x--) {
                dp[x] = max(dp[x], dp[x - w] - v);
            }
            k--;
            if (k == 0) {
                j++;
            }
            if (j >= g[w].size()) {
                break;
            }
        }
    }
    cout << *max_element(dp.begin(), dp.end());
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:35:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |             if (j >= g[w].size()) {
      |                 ~~^~~~~~~~~~~~~~

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