Submission #937784

#	Time	Username	Problem	Language	Result	Execution time	Memory
937784		Gromp15	Let's Win the Election (JOI22_ho_t3)	C++17	11 / 100	162 ms	600 KiB

Main

#include <bits/stdc++.h>
#define ll long long
#define ar array
#define db double
#define all(x) x.begin(), x.end()
#define sz(x) (int)x.size()
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define rint(l, r) uniform_int_distribution<int>(l, r)(rng)
template<typename T> bool ckmin(T &a, const T &b) { return a > b ? a = b, 1 : 0; }
template<typename T> bool ckmax(T &a, const T &b) { return a < b ? a = b, 1 : 0; }
void test_case() {
	int n, k;
	cin >> n >> k;
	vector<ar<int, 2>> a(n);
	for (auto &x : a) cin >> x[0] >> x[1];
	// let us use z people in the end
	// then, we must first take z-1 Bs, and those Bs will be taken in increasing order
	// As must be taken afterwards and can be taken in arbitrary order
	db ans = 1e18;
	int cnt = 0;
	for (int i = 0; i < n; i++) cnt += bool(~a[i][1]);
	sort(all(a), [&](const auto &A, const auto &B) { return A[1] < B[1]; });
	for (int i = 1; i <= min(cnt, k) + 1; i++) {
		// use i people in the end
		vector<db> dp(i+1, 1e18);
		dp[1] = 0;
		for (int j = 0; j < n; j++) {
			vector<db> dp2(i+1, 1e18);
			for (int l = 1; l <= i; l++) {
				if (~a[j][1] && l + 1 <= i) {
					ckmin(dp2[l+1], dp[l] + (db)a[j][1] / l);
				}
				ckmin(dp2[l], dp[l] + (db)a[j][0] / i);
			}
			swap(dp, dp2);
		}
		ckmin(ans, dp[i]);
	}
	cout << fixed << setprecision(10) << ans << '\n';
		


}
int main() {
    cin.tie(0)->sync_with_stdio(0);
    int t = 1;
//    cin >> t;
    while (t--) test_case();
}

• Subtask 1: 0 / 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