Submission #671977

#	Time	Username	Problem	Language	Result	Execution time	Memory
671977		stevancv	Knapsack (NOI18_knapsack)	C++14	100 / 100	60 ms	3860 KiB

knapsack

#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define sp ' '
#define en '\n'
#define smin(a, b) a = min(a, b)
#define smax(a, b) a = max(a, b)
using namespace std;
const int N = 1e6 + 2;
const int mod = 1e9 + 7;
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int s, n;
    cin >> s >> n;
    vector<vector<pair<int, int>>> items(s + 1);
    for (int i = 0; i < n; i++) {
        int a, b, c;
        cin >> a >> b >> c;
        items[b].push_back({a, c});
    }
    vector<pair<int, int>> v;
    for (int i = 1; i <= s; i++) {
        sort(items[i].begin(), items[i].end());
        int x = s / i;
        while (!items[i].empty() && x > 0) {
            int k = min(x, items[i].back().second);
            x -= k;
            while (k--) v.push_back({i, items[i].back().first});
            items[i].pop_back();
        }
    }
    vector<int> dp(s + 1, -1e9);
    dp[0] = 0;
    for (int i = 0; i < v.size(); i++) {
        int x = v[i].first; int y = v[i].second;
        for (int j = s; j >= x; j--) if (dp[j - x] != -1e9) smax(dp[j], dp[j - x] + y);
    }
    for (int i = 1; i <= s; i++) smax(dp[i], dp[i - 1]);
    cout << dp[s] << en;
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:36:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |     for (int i = 0; i < v.size(); i++) {
      |                     ~~^~~~~~~~~~

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