Submission #890009

#	Time	Username	Problem	Language	Result	Execution time	Memory
890009		math_pi	Knapsack (NOI18_knapsack)	C++14	100 / 100	85 ms	35412 KiB

knapsack

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

long long dp[2005][2005];
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	for(int i=0; i<2005; i++) {
		for(int j=0; j<2005; j++) {
			dp[i][j] = -2e9;
		}
	}
	int s, n;
	cin >> s >> n;
	map<int, vector<pair<int, int>>> mp;
	for(int i=0; i<n; i++) {
		int x, y, z; cin >> x >> y >> z;
		if(y <= s) {
			mp[y].push_back({x, z});
		}
	}
	int toji = 1;
	dp[0][0] = 0;
	for(auto &[x, item]: mp) {
		sort(item.begin(), item.end(), greater<pair<int, int>>());
		for(int k=0; k<=s; k++) {
			dp[toji][k] = dp[toji-1][k];
			int c = 0, i = 0, j = 0, val = 0;
			while((c+1)*1ll*x<=k && i < item.size()) {
				c++;
				val += item[i].first;
				if(dp[toji-1][k-(c*1ll*x)]!=-2e9) {
					dp[toji][k] = max(dp[toji][k], dp[toji-1][k-c*1ll*x] +val);
				}
				j++;
				if(j==item[i].second) {
					j=0;
					i++;
				}
			}
		}
		toji++;
	}
	long long res = 0;
	for(int i=0; i<=s; i++) {
		res = max(res, (long long) dp[mp.size()][i]);
	}
	cout << res << '\n';

}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:24:12: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   24 |  for(auto &[x, item]: mp) {
      |            ^
knapsack.cpp:29:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |    while((c+1)*1ll*x<=k && i < item.size()) {
      |                            ~~^~~~~~~~~~~~~

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