Submission #1288417

#	Time	Username	Problem	Language	Result	Execution time	Memory
1288417		tunademayo	Let's Win the Election (JOI22_ho_t3)	C++20	61 / 100	2595 ms	4444 KiB

Main

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

#define ll long long 
#define ld double

const bool Multitest = 0;

const int N = 505; const ll offset = 1e9;

int n, k;

struct Type 
{
	ld x, y;
}; Type a[N], b[N];

bool cmp1(Type a, Type b)
{
	return a.y < b.y || (a.y == b.y && a.x < b.x);
}
ld dp[2][N][N], f[N];

void minimize(ld& a, ld b)
{
	if(a > b) a = b;
}

ld cal(int p)
{
	for(int i = 0 ; i < 2 ; i++)
	{
		for(int j = 0 ; j <= n ; j++)
		{
			for(int cnt = 0 ; cnt <= n + 1 ; cnt++)
			{
				dp[i][j][cnt] = 1e18;
			}
		}
	}
	
	dp[0][0][1] = 0;
	
	for(int i = 0 ; i < n ; i++)
	{
		for(int j = 0 ; j <= k && j <= i ; j++)
		{
			for(int cnt = 1 ; cnt <= j + 1 && cnt <= p; cnt++)
			{
				minimize(dp[1][j][cnt], dp[0][j][cnt]);
				minimize(dp[1][j + 1][cnt], dp[0][j][cnt] + a[i + 1].x / p);
				minimize(dp[1][j + 1][cnt + 1], dp[0][j][cnt] + a[i + 1].y / cnt);
//				
//				cout << i << ' ' << j << ' ' << cnt << ' ' << dp[i][j][cnt] << '\n';
			}
		}
		swap(dp[0], dp[1]);
		for(int j = 0 ; j <= min(k, i) + 1 ; j++)
		{
			for(int cnt = 0 ; cnt <= min(j + 1, p) + 1 ; cnt++)
			{
				dp[1][j][cnt] = 1e18;
			}
		}
	}
	
	
	return f[p] = dp[0][k][p];
}

void work()
{
	cin >> n >> k;
	
	for(int i = 1 ; i <= n ; i++)
	{
		cin >> a[i].x >> a[i].y;
		if(a[i].y == -1) a[i].y = 1e9;
		f[i] = -1;
	}
	
	sort(a + 1, a + 1 + n, cmp1);
	ld ans = 1e18;
	
//	cerr << "dm";
//	
//	cout << cal(1);
////	
//	return;
	
	int l = 1, r = n, pos = n + 1;
	
	while(l <= r)
	{
		int mid = (l + r) >> 1;
		
		if(cal(mid) <= cal(mid + 1)) r = mid - 1, pos = mid;
		else l = mid + 1;
	}
	
	cout << setprecision(9) << fixed << f[pos];
}

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);	cout.tie(0);

	int q = 1;
	
	if(Multitest)	cin >> q;
	
	while(q--) work();
}

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