Submission #1027264

#	Time	Username	Problem	Language	Result	Execution time	Memory
1027264		coin_	Sure Bet (CEOI17_sure)	C++14	100 / 100	75 ms	3556 KiB

sure

#include <bits/stdc++.h>
#define int long long
using namespace std;
signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    int n;
    cin >> n;
    double a[n + 1], b[n + 1];
    for (int i = 1; i <= n; i++)
    {
        cin >> a[i] >> b[i];
    }
    sort(a + 1, a + n + 1, greater<double>());
    sort(b + 1, b + n + 1, greater<double>());
    double prefA[n + 1] = {0}, prefB[n + 1] = {0};
    prefA[1] = a[1];
    prefB[1] = b[1];
    for (int i = 2; i <= n; i++)
    {
        prefA[i] = prefA[i - 1] + a[i];
        prefB[i] = prefB[i - 1] + b[i];
    }
    double ans = 0;
    for (int i = 1; i <= n; i++)
    {
        int l = 1, r = n;
        while (r - l > 1)
        {
            int mid = l + (r - l) / 2;
            double valmid = min(prefA[i] - (double)i - (double)mid, prefB[mid] - (double)i - (double)mid);
            double valnxt = min(prefA[i] - (double)i - (double)(mid+1), prefB[mid+1] - (double)i - (double)(mid+1));

            if (valmid > valnxt)
            {
                r = mid;
            }
            else
            {
                l = mid;
            }
        }
        double vall = min(prefA[i] - (double)i - (double)l, prefB[l] - (double)i - (double)l);
        double valr = min(prefA[i] - (double)i - (double)r, prefB[r] - (double)i - (double)r);
        if (vall > valr)
        {
            ans = max(ans, vall);
        }
        else
        {
            ans = max(ans, valr);
        }
    }
    cout << fixed << setprecision(4) << ans;
}

• Subtask 1: 20 / 20
• Subtask 2: 40 / 40
• Subtask 3: 40 / 40