Submission #928603

#	Time	Username	Problem	Language	Result	Execution time	Memory
928603		jcelin	Let's Win the Election (JOI22_ho_t3)	C++14	100 / 100	884 ms	7000 KiB

Main

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

typedef long long ll;

typedef pair<int,int> ii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<ll> vll;
typedef vector<pll> vpll;

#define PB push_back
#define PF push_front
#define PPB pop_back
#define PPF pop_front
#define X first
#define Y second
#define MP make_pair
#define all(x) (x).begin(), (x).end()

const int mod = 1e9 + 7; //998244353;
const int inf = 1e9 + 7;
const ll INF = 1e18 + 7;
const int logo = 20;
const int MAXN = 700;
const int off = 1 << logo;
const int trsz = off << 1;
const int dx[] = {1, -1, 0, 0};
const int dy[] = {0, 0, -1, 1};

typedef long double ld;
typedef pair<ld, ld> pld;
const ld eps = 1e-15;

vector<pld> arr;
ld dp[MAXN][MAXN];

bool cmp(pld &a, pld &b){
	if(abs(a.Y - b.Y) > eps) return a.Y < b.Y;
	return a.X < b.X;
}

void solve(){
	int n, k;
	cin >> n >> k;
	arr.resize(n);
	for(auto &x : arr){
		cin >> x.X >> x.Y;
		if(x.Y == -1) x.Y = (ld)inf;
	}
	sort(all(arr), cmp);
	
	//L - broj pomocnika
	//R - broj obicnih
	ld ans = inf;
	for(int L=0; L<=k; L++){			
		for(int i=0; i<=n; i++) for(int j=0; j<=n; j++) dp[i][j] = (ld)inf;
		dp[0][0] = 0;
		
		for(int i=1; i<=n; i++){
			pld cur = arr[i - 1];
			for(int R=0; R<=min(i, k - L); R++){
				int clef = i - R;
				if(R) dp[i][R] = min(dp[i][R], dp[i - 1][R - 1] + (ld)cur.X / (ld)(L + 1));
				
				if(clef <= L) dp[i][R] = min(dp[i][R], dp[i - 1][R] + (ld)cur.Y / (ld)clef);
				else dp[i][R] = min(dp[i][R], dp[i - 1][R]);
			}
		}
		ans = min(ans, dp[n][k - L]);
	}
	
	cout << fixed << setprecision(10) << ans << "\n";
}

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	int tt = 1;
	//cin >> tt;
	while(tt--) solve();
	return 0;
}

• 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