Submission #642672

#	Time	Username	Problem	Language	Result	Execution time	Memory
642672		ymm	Sure Bet (CEOI17_sure)	C++17	100 / 100	94 ms	3608 KiB

sure

#include <bits/stdc++.h>
#define Loop(x,l,r) for (ll x = (l); x < (r); ++x)
#define LoopR(x,l,r) for (ll x = (r)-1; x >= (l); --x)
typedef long long ll;
typedef std::pair<int, int> pii;
typedef std::pair<ll , ll > pll;
using namespace std;

const int N = 100'010;
double a[N], b[N];
int n;

template<class T>
pair<double, int> ter(T f, int l, int r)
{
	--r;
	while (l < r) {
		int m = (l+r)/2;
		if (f(m) < f(m+1))
			l = m+1;
		else
			r = m;
	}
	return {f(l), l};
}

int main()
{
	cin.tie(0) -> sync_with_stdio(false);
	cin >> n;
	Loop (i,1,n+1) {
		cin >> a[i] >> b[i];
	}
	sort(a+1, a+n+1); reverse(a+1, a+n+1);
	sort(b+1, b+n+1); reverse(b+1, b+n+1);
	Loop (i,0,n) {
		a[i+1] += a[i];
		b[i+1] += b[i];
	}
	reverse(b, b+n+1);
	double ans = 0;
	Loop (j,0,n+1) {
		auto [x, i] = ter([&](int i){return min(a[i], b[j+i]);}, 0, n+1-j);
		ans = max(ans, x - (n - j));
	}
	Loop (i,1,n+1) {
		auto [x, j] = ter([&](int j){return min(a[i+j], b[j]);}, 0, n+1-i);
		ans = max(ans, x - (n + i));
	}
	cout << fixed << setprecision(4) << ans << '\n';
}

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