Submission #131552

#	Time	Username	Problem	Language	Result	Execution time	Memory
131552		SamAnd	Sure Bet (CEOI17_sure)	C++17	100 / 100	125 ms	5272 KiB

sure

#include <bits/stdc++.h>
using namespace std;
const int N = 100005;

int n;
double a[N], b[N];
double sa[N], sb[N];

double ans;

int main()
{
    ios_base::sync_with_stdio(false);
    cout.setf(ios::fixed);
    cout.setf(ios::showpoint);
    cout.precision(4);
    cin >> n;
    for (int i = 1; i <= n; ++i)
    {
        cin >> a[i] >> b[i];
    }
    sort(a + 1, a + n + 1);
    sort(b + 1, b + n + 1);
    for (int i = n; i >= 1; --i)
    {
        sa[i] = sa[i + 1] + a[i];
        sb[i] = sb[i + 1] + b[i];
    }
    double ans = 0;
    for (int i = n; i >= 1; --i)
    {
        int l = 1, r = n;
        while ((r - l) > 3)
        {
            int m = (l + r) / 2;
            if ((sa[i] - (n - i + 1) - (n - m + 1)) <= (sb[m] - (n - i + 1) - (n - m + 1)))
                l = m;
            else
                r = m;
        }
        for (int m = max(1, l - 5); m <= min(n, r + 5); ++m)
        {
            ans = max(ans, min((sa[i] - (n - i + 1) - (n - m + 1)), (sb[m] - (n - i + 1) - (n - m + 1))));
        }
    }
    cout << ans << endl;
    return 0;
}

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