Submission #528915

#	Time	Username	Problem	Language	Result	Execution time	Memory
528915		FireGhost1301	Let's Win the Election (JOI22_ho_t3)	C++11	100 / 100	261 ms	2396 KiB

Main

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

const int N = 500 + 3;
const double inf = 1e6 + 3;
int n, k, a[N], b[N], p[N];
double f[N][N];

double calc(int m) {
    for (int i = 1; i <= n; ++i) {
        for (int j = 0; j <= i; ++j) {
            f[i][j] = inf;
            if (j) f[i][j] = min(f[i][j], f[i - 1][j - 1] + (double)a[p[i]] / (m + 1));
            if (j < i) {
                if (i - j - 1 < m) f[i][j] = min(f[i][j], f[i - 1][j] + (double)b[p[i]] / (i - j));
                else f[i][j] = min(f[i][j], f[i - 1][j]);
            }
        }
    }
    return f[n][k - m];
}

void solve() {
    cin >> n >> k;
    for (int i = 1; i <= n; ++i) {
        cin >> a[i] >> b[i];
        if (b[i] == -1) b[i] = INT_MAX;
    }

    iota(p + 1, p + n + 1, 1);
    sort(p + 1, p + n + 1, [&](int i, int j) {
        if (b[i] != b[j]) return b[i] < b[j];
        return a[i] < a[j];
    });
    
    double ans = inf;
    for (int i = 0; i <= k; ++i)
        ans = min(ans, calc(i));

    cout << ans;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout << setprecision(15) << fixed;
    solve();
    return 0;
}

• 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