Submission #866577

#	Time	Username	Problem	Language	Result	Execution time	Memory
866577		NotLinux	Let's Win the Election (JOI22_ho_t3)	C++17	100 / 100	1834 ms	4440 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N = 505;
const int inf = 1ll << 60;
int n,k,a[N],b[N];
long double eval(int x){
	if((k-x) < 0){
		return inf;
	}
	long double dp[n+2][n+2];
	for(int i = 0;i<=n;i++){
		for(int j = 0;j<=n;j++){
			dp[i][j] = 1e18 + 7;
		}
	}
	dp[0][0] = 0;
	for(int i = 0;i<n;i++){
		for(int j = 0;j<=n;j++){
			//ai alır
			dp[i+1][j+1] = min(dp[i+1][j+1] , dp[i][j] + (long double)a[i] / (long double)(x+1));
			//bi  / almaz
			if((i+1-j) <= x){
				dp[i+1][j] = min(dp[i+1][j] , dp[i][j] + (long double)b[i] / (long double)(i+1-j));
			}
			else {
				dp[i+1][j] = min(dp[i+1][j] , dp[i][j]);
			}
		}
	}
	return dp[n][k-x];
}
void solve(){
	cin >> n >> k;
	pair < int , int > arr[n];
	int sayac = n;
	for(int i = 0;i<n;i++){
		cin >> arr[i].second >> arr[i].first;
		if(arr[i].first == -1){
			arr[i].first = inf;
			sayac--;
		}
	}
	sort(arr , arr + n);
	for(int i = 0;i<n;i++){
		a[i] = arr[i].second;
		b[i] = arr[i].first;
	}
	long double ans = 1e18 + 7;
	for(int i = 0;i<=sayac;i++){
		ans = min(ans , eval(i));
	}
	cout << fixed << setprecision(9) << ans << endl;
}
signed main(){
	ios_base::sync_with_stdio(0);cin.tie(0);
	int testcase = 1;//cin >> testcase;
	while(testcase--)solve();
}
/*

obs1 : almadıklarımdan ilk x tanesini kesin alcam
dp[i][j] -> şimdiye kadar kaç tane aldım

*/

• 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