Submission #1253520

#	Time	Username	Problem	Language	Result	Execution time	Memory
1253520		norman165	Let's Win the Election (JOI22_ho_t3)	C++20	0 / 100	2596 ms	980 KiB

Main

#include <bits/stdc++.h>

#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define int long long
#define yes() cout << "YES\n"
#define no() cout << "NO\n"

using namespace std;
using ll = long long;
using ull = unsigned long long;
using ld = long double;

const int inf = 1e18;
const int mod = 1e9 + 7;
const int maxn = 1e6 + 10;
const int mod1 = 998244353;
const int mod2 = 1e18 + 1;
const int mod3 = 1e9 + 9;
const int mod4 = 333333333;
const int mod5 = 200000;
const int mod6 = 10007;
const int k = 300;
const int w = 1e5;
const ld EPS = 1e-8;

int LOG = 30;

void solve() {
    int n, k1;
    cin >> n >> k1;

    vector<pair<ld, ld>> a(n);
    for (auto& i : a) {
        cin >> i.first >> i.second;
        if (i.second == -1) i.second = inf;
    }

    sort(all(a), [](pair<ld, ld> a, pair<ld, ld> b) {
        return a.second < b.second || (a.second == b.second && a.first < b.first);
    });

    ld ans = inf;
    auto f = [&](int x) {
        if (x == 0) {
            vector<int> mn;
            for (int i = 0; i < n; i++) mn.push_back(a[i].first);
            sort(all(mn));

            ld res = 0;
            for (int i = 0; i < k1; i++) res += mn[i];
            return res;
        }

        vector<vector<ld>> dp(n, vector<ld> (x + 1, inf));
        for (int i = 0; i < n; i++) dp[i][0] = 0;
        dp[0][1] = a[0].second;

        for (int k = 1; k <= x; k++) {
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < i; j++) {
                    ld gol = dp[j][k - 1] + a[i].second / ld(k);
                    dp[i][k] = min(dp[i][k], gol);
                }
            }
        }

        ld res = inf;
        for (int i = 0; i < n; i++) {
            for (int j = 1; j <= x; j++) {
                ld tmp = dp[i][j];
                if (j < k1) {
                    ld ost = k1 - j;
                    vector<ld> mn;

                    for (int k = i + 1; k < n; k++) mn.push_back(a[k].first);
                    sort(all(mn));
                    if (mn.size() < ost) continue;
                    ld l = j + 1;
                    for (int k = 0; k < ost; k++) tmp += mn[k] / l;
                }

                res = min(res, tmp);
            }
        }

        return res;
    };

    for (int i = 0; i < n; i++) ans = min(ans, f(i));
    cout << ans << "\n";
}

signed main() {
    cout.precision(16);

    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t = 1;
    // cin >> t;

    while (t--) {
        solve();
    }
}

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