Submission #200179

#	Time	Username	Problem	Language	Result	Execution time	Memory
200179		alishahali1382	Sure Bet (CEOI17_sure)	C++14	100 / 100	1205 ms	5368 KiB

sure

#include <bits/stdc++.h>
#pragma GCC optimize ("O2")
#pragma GCC optimize ("unroll-loops")
//#pragma GCC optimize("no-stack-protector,fast-math")

using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<pii, int> piii;
typedef pair<ll, ll> pll;
#define debug(x) cerr<<#x<<'='<<(x)<<endl;
#define debugp(x) cerr<<#x<<"= {"<<(x.first)<<", "<<(x.second)<<"}"<<endl;
#define debug2(x, y) cerr<<"{"<<#x<<", "<<#y<<"} = {"<<(x)<<", "<<(y)<<"}"<<endl;
#define debugv(v) {cerr<<#v<<" : ";for (auto x:v) cerr<<x<<' ';cerr<<endl;}
#define all(x) x.begin(), x.end()
#define pb push_back
#define kill(x) return cout<<x<<'\n', 0;

const ld eps=1e-7;
const int inf=1000000010;
const ll INF=10000000000000010LL;
const int mod = 1000000007;
const int MAXN = 100010, LOG=20;

int n, m, k, u, v, x, y, t, a, b;
ld A[MAXN];
ld B[MAXN];

int get(ld val){
	if (val>min(A[n], B[n])) return inf;
	int x=lower_bound(A, A+n+1, val)-A;
	int y=lower_bound(B, B+n+1, val)-B;
	return x+y;
}

int main(){
	ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	//freopen("input.txt", "r", stdin);
	//freopen("output.txt", "w", stdout);
	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);
	reverse(A+1, A+n+1);
	reverse(B+1, B+n+1);
	for (int i=2; i<=n; i++) A[i]+=A[i-1], B[i]+=B[i-1];
	
	ld ans=0;
	for (int i=1; i<=2*n; i++){
		ld dwn=0, up=min(A[n], B[n]);
		while (up-dwn>1e-5){
			ld mid=(dwn+up)/2;
			if (get(mid)>i) up=mid;
			else dwn=mid;
		}
		ans=max(ans, dwn-i);
	}
	cout<<setprecision(4)<<fixed<<ans<<'\n';
	
	return 0;
}

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