Submission #1278007

#	Time	Username	Problem	Language	Result	Execution time	Memory
1278007		mingga	Let's Win the Election (JOI22_ho_t3)	C++20	100 / 100	162 ms	2424 KiB

Main

// Author: caption_mingle
#include "bits/stdc++.h"

using namespace std;

#define ln "\n"
#define pb push_back
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int)(x).size())
#define ll long long
const int mod = 1e9 + 7;
const int inf = 2e9;
const int N = 505;
int n, k;
double dp[N][N];
pair<int, int> d[N];

signed main() {
	cin.tie(0) -> sync_with_stdio(0);
	#define task ""
	if(fopen(task ".INP", "r")) {
		freopen(task ".INP", "r", stdin);
		freopen(task ".OUT", "w", stdout);
	}
	cin >> n >> k;
	for(int i = 1; i <= n; i++) {
		int a, b; cin >> a >> b;
		if(b == -1) b = inf;
		d[i] = {b, a};
	}
	sort(d + 1, d + n + 1);
	double ans = inf;
	for(int i = 0; i <= k; i++) {
		for(int j = 0; j <= n; j++) {
			for(int t = 0; t <= k; t++) {
				dp[j][t] = 2e9;
			}
		}
		dp[0][0] = 0;
		// cerr << "TURN " << i << ln;
		for(int j = 1; j <= n; j++) {
			for(int t = 0; t <= j; t++) {
				if(t > 0) dp[j][t] = min(dp[j][t], dp[j - 1][t - 1] + d[j].se / (double)(i + 1));
				if(j - t <= i) {
					dp[j][t] = min(dp[j][t], dp[j - 1][t] + d[j].fi / (double)(j - t));
				} else {
					dp[j][t] = min(dp[j][t], dp[j - 1][t]);
				}
				// cerr << j << ' ' << t << ' ' << dp[j][t] << ln;
			}
		}
		ans = min(ans, dp[n][k - i]);
	}
	cout << setprecision(6) << fixed << ans << ln;
    cerr << "\nTime: " << clock() * 1000 / CLOCKS_PER_SEC;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:24:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |                 freopen(task ".INP", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:25:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   25 |                 freopen(task ".OUT", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• 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