Submission #679663

#	Time	Username	Problem	Language	Result	Execution time	Memory
679663		nicolexxuu	Knapsack (NOI18_knapsack)	C++17	100 / 100	138 ms	17484 KiB

knapsack

#include <bits/stdc++.h>

using namespace std;

int main() {
	int S, N;
	cin >> S >> N;
	
	map<int, vector<pair<int, int>>> by_weight;
	for(int t = 0; t < N; t++) {
		int V, W, K;
		cin >> V >> W >> K;
		by_weight[W].push_back({V, K});
	}
	
	vector<vector<int>> dp(by_weight.size()+1, vector<int>(S+1));
	
	int res = 0;
	int i = 1;
	for(auto hi : by_weight) {
		auto w = hi.first;
		auto items = hi.second;
		sort(items.begin(), items.end(), greater<pair<int, int>>());
		for(int s = 1; s <= S; s++) {
			dp[i][s] = dp[i-1][s];
			
			int curr_i = 0, curr_cnt = 0, val = 0;
			for(int cnt = 1; cnt * w <= s && curr_i < items.size(); cnt++) {
				val += items[curr_i].first;
				if(++curr_cnt == items[curr_i].second) {
					curr_cnt = 0;
					curr_i++;
				}
				dp[i][s] = max(dp[i][s], dp[i-1][s-cnt*w] + val);
			}
		}
		
		res = max(dp[i][S], res);
		i++;
	}
	
	cout << res << endl;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:28:44: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |    for(int cnt = 1; cnt * w <= s && curr_i < items.size(); cnt++) {
      |                                     ~~~~~~~^~~~~~~~~~~~~~

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