Submission #939305

#	Time	Username	Problem	Language	Result	Execution time	Memory
939305		Litusiano	Let's Win the Election (JOI22_ho_t3)	C++17	0 / 100	2531 ms	800 KiB

Main

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define endl "\n"
const int INF = 1e18;
mt19937 rng((unsigned int) chrono::steady_clock::now().time_since_epoch().count());

bool cmp(pair<int,int> a, pair<int,int> b){
	if(a.second == b.second) return a.first<b.first;
	return a.second < b.second;
}


signed main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout<<setprecision(3)<<fixed;
	int n,k1; cin>>n>>k1;

	vector<pair<int,int>> v(n);
	for(int i = 0; i<n; i++){
		cin>>v[i].first>>v[i].second;
		if(v[i].second == -1) v[i].second = INF;
	}
	long double ans = INF;
	for(int x = 0; x <= k1; x++){
		int buy = k1-x;
		// cheaper way to buy buy
		vector<long double> dp(x+1, INF);
		vector<pair<int,int>> act = v;
		map<pair<int,int>, int> curinsum, curinb, tot;
		sort(act.begin(),act.end());
		for(auto y : act) tot[y]++;
		dp[0] = 0;
		for(int i = 0; i<buy; i++) dp[0] += 1.0 * act[i].first / (x+1), curinsum[act[i]]++;
		for(int i = 1; i <= x; i++){
			pair<int,int> bst; long double best = INF;
			pair<int,int> bst1;
			for(auto y : act){
				if(y.second == -1) continue;
				// buying this 
				if(tot[y] == curinb[y]) continue;
				// can make the transition
				if(tot[y] == curinb[y] + curinsum[y]){
					// retreat from the sum
					long double cur = dp[i-1] - 1.0*y.first/(x+1) + 1.0*y.second/i; // now take the other minimum(just bruteforce for now)
					for(auto z : tot){
						if(z.second == curinb[z.first] + curinsum[z.first]) continue;
						long double tmp = cur + 1.0*z.first.first/(x+1);
						if(tmp < best){
							best = tmp;
							bst = y;
							bst1 = z.first;
						}
					}
				}
				else{
					long double tmp = dp[i-1] + 1.0*y.second/(i);
					if(tmp < best){
						best = tmp;
						bst = y;
						bst1 = {-1,-1};
					}
				}

			}
			if(best == INF) continue;
			curinb[bst]++;
			if(bst1.first != -1) curinsum[bst]--,curinsum[bst1]++;
			dp[i] = best;
		}
		// cerr<<dp[x]<<" ";
		ans = min(ans, dp[x]); // having bought x collaborators
	}
	cout<<ans<<endl;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 5
• Subtask 3: 0 / 11
• Subtask 4: 0 / 12
• Subtask 5: 0 / 33
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23