Submission #924030

#	Time	Username	Problem	Language	Result	Execution time	Memory
924030		goodspeed0208	Let's Win the Election (JOI22_ho_t3)	C++14	100 / 100	400 ms	3056 KiB

Main

#include<bits/stdc++.h>
#define pii pair<int, int>
#define INF 5000000
using namespace std;
 
bool cmp(pii a, pii b) {
	if (a.second == -1 && b.second == -1) return a.first < b.first;
	if (a.second == -1) return (1 > 2);
	if (b.second == -1) return (1 < 2);
	if (a.second == b.second) return a.first > b.first;
	return a.second < b.second;
}
 
signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	int n, K;
	cin >> n >> K;
	vector<pii>v(n+1);
	vector<double>a(n+1), b(n+1);
	for (int i = 1 ; i <=  n ;i++) cin >> v[i].first >> v[i].second;
	sort(v.begin()+1, v.end(), cmp);
	for (int i = 1 ; i <= n ;i++) a[i] = (double)v[i].first, b[i] = (double)v[i].second;
	//vector<vector<vector<double> > >dp(505, vector<vector<double> >(505, vector<double>(505, INF)) );
	//dp[0][0][1] = 0.0;
	
	double ans = INF;
    
    multiset<int>st;
    vector<double>w(n+2, 0);
    for (int i = n ; i >= 1 ; i--) {
        st.insert(a[i]);
        int k = 0;
        for (auto j : st) {
            if (k >= K-(i-1)) break;
            w[i] += j;
            k++;
            
        }
    }
    //for (int i = 1 ; i <= n ; i++) cout << w[i] << " ";
    //cout << "\n";
    ans = w[1];
    for (int help = 1 ; help <= K+1 ; help++) {
        vector<vector<double> >dp(505, vector<double>(505, INF));
        dp[0][1] = 0;
        //cout << "help" << " " << help << ": \n";
        for (int i = 1 ; i <= n ; i++) {//first i people
            //cout << i << ": ";
    		for (int k = 1 ; k <= min(i+1, help) ; k++) {// get how many people
    			dp[i][k] = dp[i-1][k] + (a[i] / help);
    			if (k > 1 && b[i] != -1) dp[i][k] = min(dp[i][k], dp[i-1][k-1] + b[i] / (k-1));
    			//cout << dp[i][k] <<" ";
    			
    			if (k == help) {
        		    ans = min(ans, dp[i][help] + w[i+1] / help);
        		    //cout << "ans: " << dp[i][help] << "+" << w[i+1] / help << "\n";
        		}
    			
    		}
    		//cout << "\n";
    	}
    	//for (int i = 0)
    }
        
	
	cout << fixed << setprecision(6) << ans << "\n";
	//for (auto &i : v) cout << i.first <<" " << i.second << "\n";
}

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