Submission #919576

#	Time	Username	Problem	Language	Result	Execution time	Memory
919576		tvladm2009	Let's Win the Election (JOI22_ho_t3)	C++17	16 / 100	45 ms	4440 KiB

Main

#include <iostream>
#include <complex>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <numeric>
#include <cstring>
#include <ctime>
#include <cstdlib>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <list>
#include <cmath>
#include <bitset>
#include <cassert>
#include <queue>
#include <stack>
#include <deque>
#include <random>
#include <iomanip>
 
using namespace std;
template<typename T1, typename T2> inline void chkmin(T1 &a, T2 b) {if (a > b) a = b;}
template<typename T1, typename T2> inline void chkmax(T1 &a, T2 b) {if (a < b) a = b;}
#define files(FILENAME) read(FILENAME); write(FILENAME)
#define read(FILENAME) freopen((FILENAME + ".in").c_str(), "r", stdin)
#define write(FILENAME) freopen((FILENAME + ".out").c_str(), "w", stdout)
#define all(c) (c).begin(), (c).end()
#define sz(c) (int)(c).size()
#define left left228
#define right right228
#define y1 y1228
#define mp make_pair
#define pb push_back
#define y2 y2228
#define rank rank228
using ll = long long;
using ld = long double; 
const string FILENAME = "input";
const int MAXN = 500 + 7;

int n, k;
pair<int, int> a[MAXN];
ld dp[MAXN][MAXN];

ld f(int kek) {
	for (int i = 0; i <= n; i++) {
		for (int j = 0; j <= n; j++) {
			dp[i][j] = 1e9;
		}
	}
	dp[0][0] = 0;
	for (int i = 1; i <= n; i++) {
		for (int j = 0; j <= i; j++) {
			int c = i - j;
			if (c <= kek && i - j != 0) {
				chkmin(dp[i][j], dp[i - 1][j] + (ld) a[i].first / (ld) c);
			} else if (c > kek) {
				chkmin(dp[i][j], dp[i - 1][j]);
			}
			if (j >= 1) {
				chkmin(dp[i][j], dp[i - 1][j - 1] + (ld) a[i].second / (ld) (kek + 1));
			}
		}
	}
	return dp[n][k - kek];
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	//read(FILENAME);
	cout << setprecision(10) << fixed;
	cin >> n >> k;
	for (int i = 1; i <= n; i++) {
		cin >> a[i].second >> a[i].first;
	}
	for (int i = 1; i <= n; i++) {
		if (a[i].first == -1) {
			a[i].first = 1e9;
		}
	}
	sort(a + 1, a + n + 1);
	int l = 1, r = n, sol = 0;
	while (l <= r) {
		int m = (l + r) >> 1;
		if (f(m) < f(m - 1)) {
			l = m + 1;
			sol = m;
		} else {
			r = m - 1;
		}
	}
	ld res = min(f(sol), f(0));
	res = (ld) ((ld) res * (ld) 1e10) / (ld) 1e10;
	cout << res << '\n';
	return 0;				
}

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