Submission #1263006

#	Time	Username	Problem	Language	Result	Execution time	Memory
1263006		khanghb2006	Knapsack (NOI18_knapsack)	C++20	100 / 100	188 ms	33256 KiB

knapsack

#include<bits/stdc++.h>
using namespace std;
#define TASK "task"

const int mxN = 2e3 + 7;
const int inf = 1e9 + 67;

int n;
int s;
long long dp[mxN][mxN];
vector<pair<int,int>>groups[mxN];

void solve(void) {
	cin >> s >> n;
	for (int i = 1; i <= n; i++) {
		int v , w , k;
		cin >> v >> w >> k;
		groups[w].push_back(make_pair(v , k));
	}
	for (int i = 0; i <= s; i++)
		sort(groups[i].begin() , groups[i].end() , greater<pair<int,int>>());
	for (int i = 1; i <= s; i++) {
		for (int j = 0; j <= s; j++)
			dp[i][j] = dp[i - 1][j];
		if(!groups[i].size()) continue;
		// với cân nặng i thì chỉ có thể lấy nhiều nhất S / i cái
		for (int j = s; j >= 0; j--) {
			int w = 0;
			long long v = 0;
			for (auto it : groups[i]) {
				int k = it.second;
				while(k > 0 && w <= j) {
					w += i;
					v += it.first;
					--k;
					if(j >= w) dp[i][j] = max(dp[i][j] , dp[i - 1][j - w] + v);
				}
			}
		}
	}
	long long ans = -inf;
	for (int i = 0; i <= s; i++)
	for (int j = 0; j <= s; j++)
		ans = max(ans , dp[i][j]);
	cout << ans;
}

int main() {
	ios_base :: sync_with_stdio(0);
	cin.tie(0);
	//freopen(TASK".inp","r",stdin);
	//freopen(TASK".out","w",stdout);
	int tc = 1;
	//cin >> tc;
	while(tc--) solve();
	return 0;
}

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