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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#82167#5570. Epidemic Escapeheno239WA 10ms12252kbC++1712.8kb2023-02-27 10:14:012023-02-27 10:14:05

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2023-02-27 10:14:05]
  • 评测
  • 测评结果:WA
  • 用时:10ms
  • 内存:12252kb
  • [2023-02-27 10:14:01]
  • 提交

answer

#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<unordered_set>
#include<utility>
#include<cassert>
#include<complex>
#include<numeric>
#include<array>
#include<chrono>
using namespace std;

//#define int long long
typedef long long ll;

typedef unsigned long long ul;
typedef unsigned int ui;
//ll mod = 1;
constexpr ll mod = 998244353;
//constexpr ll mod = 1000000007;
const ll INF = mod * mod;
typedef pair<int, int>P;

#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
#define all(v) (v).begin(),(v).end()
typedef pair<ll, ll> LP;

template<typename T>
void chmin(T& a, T b) {
	a = min(a, b);
}
template<typename T>
void chmax(T& a, T b) {
	a = max(a, b);
}
template<typename T>
vector<T> vmerge(vector<T>& a, vector<T>& b) {
	vector<T> res;
	int ida = 0, idb = 0;
	while (ida < a.size() || idb < b.size()) {
		if (idb == b.size()) {
			res.push_back(a[ida]); ida++;
		}
		else if (ida == a.size()) {
			res.push_back(b[idb]); idb++;
		}
		else {
			if (a[ida] < b[idb]) {
				res.push_back(a[ida]); ida++;
			}
			else {
				res.push_back(b[idb]); idb++;
			}
		}
	}
	return res;
}
template<typename T>
void cinarray(vector<T>& v) {
	rep(i, v.size())cin >> v[i];
}
template<typename T>
void coutarray(vector<T>& v) {
	rep(i, v.size()) {
		if (i > 0)cout << " "; cout << v[i];
	}
	cout << "\n";
}
ll mod_pow(ll x, ll n, ll m = mod) {
	if (n < 0) {
		ll res = mod_pow(x, -n, m);
		return mod_pow(res, m - 2, m);
	}
	if (abs(x) >= m)x %= m;
	if (x < 0)x += m;
	//if (x == 0)return 0;
	ll res = 1;
	while (n) {
		if (n & 1)res = res * x % m;
		x = x * x % m; n >>= 1;
	}
	return res;
}
//mod should be <2^31
struct modint {
	int n;
	modint() :n(0) { ; }
	modint(ll m) {
		if (m < 0 || mod <= m) {
			m %= mod; if (m < 0)m += mod;
		}
		n = m;
	}
	operator int() { return n; }
};
bool operator==(modint a, modint b) { return a.n == b.n; }
bool operator<(modint a, modint b) { return a.n < b.n; }
modint operator+=(modint& a, modint b) { a.n += b.n; if (a.n >= mod)a.n -= (int)mod; return a; }
modint operator-=(modint& a, modint b) { a.n -= b.n; if (a.n < 0)a.n += (int)mod; return a; }
modint operator*=(modint& a, modint b) { a.n = ((ll)a.n * b.n) % mod; return a; }
modint operator+(modint a, modint b) { return a += b; }
modint operator-(modint a, modint b) { return a -= b; }
modint operator*(modint a, modint b) { return a *= b; }
modint operator^(modint a, ll n) {
	if (n == 0)return modint(1);
	modint res = (a * a) ^ (n / 2);
	if (n % 2)res = res * a;
	return res;
}

ll inv(ll a, ll p) {
	return (a == 1 ? 1 : (1 - p * inv(p % a, a)) / a + p);
}
modint operator/(modint a, modint b) { return a * modint(inv(b, mod)); }
modint operator/=(modint& a, modint b) { a = a / b; return a; }
const int max_n = 1 << 20;
modint fact[max_n], factinv[max_n];
void init_f() {
	fact[0] = modint(1);
	for (int i = 0; i < max_n - 1; i++) {
		fact[i + 1] = fact[i] * modint(i + 1);
	}
	factinv[max_n - 1] = modint(1) / fact[max_n - 1];
	for (int i = max_n - 2; i >= 0; i--) {
		factinv[i] = factinv[i + 1] * modint(i + 1);
	}
}
modint comb(int a, int b) {
	if (a < 0 || b < 0 || a < b)return 0;
	return fact[a] * factinv[b] * factinv[a - b];
}
modint combP(int a, int b) {
	if (a < 0 || b < 0 || a < b)return 0;
	return fact[a] * factinv[a - b];
}

ll gcd(ll a, ll b) {
	a = abs(a); b = abs(b);
	if (a < b)swap(a, b);
	while (b) {
		ll r = a % b; a = b; b = r;
	}
	return a;
}
using ld = long double;
//typedef long double ld;
typedef pair<ld, ld> LDP;
const ld eps = 1e-6;
const ld pi = acosl(-1.0);
template<typename T>
void addv(vector<T>& v, int loc, T val) {
	if (loc >= v.size())v.resize(loc + 1, 0);
	v[loc] += val;
}
/*const int mn = 2000005;
bool isp[mn];
vector<int> ps;
void init() {
	fill(isp + 2, isp + mn, true);
	for (int i = 2; i < mn; i++) {
		if (!isp[i])continue;
		ps.push_back(i);
		for (int j = 2 * i; j < mn; j += i) {
			isp[j] = false;
		}
	}
}*/

//[,val)
template<typename T>
auto prev_itr(set<T>& st, T val) {
	auto res = st.lower_bound(val);
	if (res == st.begin())return st.end();
	res--; return res;
}

//[val,)
template<typename T>
auto next_itr(set<T>& st, T val) {
	auto res = st.lower_bound(val);
	return res;
}
using mP = pair<modint, modint>;
mP operator+(mP a, mP b) {
	return { a.first + b.first,a.second + b.second };
}
mP operator+=(mP& a, mP b) {
	a = a + b; return a;
}
mP operator-(mP a, mP b) {
	return { a.first - b.first,a.second - b.second };
}
mP operator-=(mP& a, mP b) {
	a = a - b; return a;
}
LP operator+(LP a, LP b) {
	return { a.first + b.first,a.second + b.second };
}
LP operator+=(LP& a, LP b) {
	a = a + b; return a;
}
LP operator-(LP a, LP b) {
	return { a.first - b.first,a.second - b.second };
}
LP operator-=(LP& a, LP b) {
	a = a - b; return a;
}

mt19937 mt(time(0));

const string drul = "DRUL";
string senw = "SENW";
//DRUL,or SENW
int dx[4] = { 1,0,-1,0 };
int dy[4] = { 0,1,0,-1 };

//-----------------------------------------

typedef complex<ld> Point;
ld dot(Point a, Point b) { return real(conj(a) * b); }
ld cross(Point a, Point b) { return imag(conj(a) * b); }
namespace std {
	bool operator<(const Point& lhs, const Point& rhs) {
		return lhs.real() == rhs.real() ? lhs.imag() < rhs.imag() : lhs.real() < rhs.real();
	}
}
struct Line {
	Point a, b;
};
struct Circle {
	Point p; ld r;
};
int ccw(Point a, Point b, Point c) {
	b -= a; c -= a;
	if (cross(b, c) > eps)return 1;//counter clockwise
	if (cross(b, c) < -eps)return -1;//clock wise
	if (dot(b, c) < 0)return 2;//c--a--b on line
	if (norm(b) < norm(c))return -2;//a--b--c on line
	return 0; //a--c--b on line
}
bool eq(ld a, ld b) {
	return abs(a - b) < eps;
}
//2直線の交差判定
bool isis_ll(Line l, Line m) {
	return !eq(cross(l.b - l.a, m.b - m.a), 0);
}
//直線と線分の交差判定
bool isis_ls(Line l, Line s) {
	return (cross(l.b - l.a, s.a - l.a) * cross(l.b - l.a, s.b - l.a) < eps);
}
//点が直線上に存在するか
bool isis_lp(Line l, Point p) {
	return (abs(cross(l.b - p, l.a - p)) < eps);
}
//点が線分上に存在するか
bool isis_sp(Line s, Point p) {
	//誤差がisis_lpに比べて大きいので、できるだけisis_lpを使う
	return (abs(s.a - p) + abs(s.b - p) - abs(s.b - s.a) < eps);
}
//線分と線分の交差判定
//bool isis_ss(Line s, Line t) {
//	return(cross(s.b - s.a, t.a - s.a)*cross(s.b - s.a, t.b - s.a) < -eps && cross(t.b - t.a, s.a - t.a)*cross(t.b - t.a, s.b - t.a) < -eps);
//}
//線分と線分の交差判定2
//本当にそれは線分ですか?(check {(0,0),(2,0)},{(1,0),(1,0)})
bool isis_ss(Line s, Line t) {
	return ccw(s.a, s.b, t.a) * ccw(s.a, s.b, t.b) <= 0 && ccw(t.a, t.b, s.a) * ccw(t.a, t.b, s.b) <= 0;
}
//点から直線への垂線の足
Point proj(Line l, Point p) {
	ld t = dot(p - l.a, l.a - l.b) / norm(l.a - l.b);
	return l.a + t * (l.a - l.b);
}
//直線と直線の交点
//平行な2直線に対しては使うな!!!!
Point is_ll(Line s, Line t) {
	Point sv = s.b - s.a; Point tv = t.b - t.a;
	return s.a + sv * cross(tv, t.a - s.a) / cross(tv, sv);
}

void solve() {
	int n; cin >> n;
	vector<LP> p(n);
	int c0 = 0;
	rep(i, n) {
		int x, y; cin >> x >> y;
		x *= 2; y *= 2;
		p[i] = { x,y };
		if (x == 0 && y == 0) {
			c0++;
		}
	}
	vector<Point> vp(n);
	rep(i, n)vp[i] = { (ld)p[i].first,(ld)p[i].second };
	vector<Line> lp(n);
	rep(i, n) {
		if (p[i] == LP{ 0,0 })continue;
		int x = p[i].first, y = p[i].second;
		lp[i].a = { (ld)x,(ld)y };
		lp[i].b = { (ld)(x - y),(ld)(y + x) };
	}
	vector<ld> pt(n);
	rep(i, n) {
		if (p[i] == LP{ 0,0 })continue;
		pt[i] = atan2(p[i].second, p[i].first);
	}
	auto comp = [&](int i, int j) {
		return pt[i] < pt[j];
	};
	vector<int> ids;
	rep(i, n) {
		if (p[i] == LP{ 0,0 })continue;
		ids.push_back(i);
	}
	auto check = [&](int i, int j, int k) {
		if (ccw(vp[i], { 0,0 }, vp[j]) != -1)return true;
		Point pm = is_ll(lp[i], lp[k]);
		if (ccw(lp[j].a, lp[j].b, pm) == -1)return true;
		else return false;
	};
	sort(all(ids), comp);
	vector<vector<int>> vs;
	rep(_, 5) {
		if (ids.empty())continue;
		ll mi = INF;
		int ci = -1;
		rep(i, ids.size()) {
			int id = ids[i];
			ll dx = p[id].first;
			ll dy = p[id].second;
			ll d = dx * dx + dy * dy;
			if (d < mi) {
				mi = d;
				ci = i;
			}
		}
		vector<int> nids;
		Rep(i, ci, ids.size()) {
			int id = ids[i];
			while (nids.size() >= 2 && !check(nids[nids.size() - 2], nids[nids.size() - 1], id)) {
				nids.pop_back();
			}
			nids.push_back(id);
		}
		rep(i, ci + 1) {
			int id = ids[i];
			while (nids.size() >= 2 && !check(nids[nids.size() - 2], nids[nids.size() - 1], id)) {
				nids.pop_back();
			}
			nids.push_back(id);
		}
		nids.pop_back();
		vs.push_back(nids);
		vector<bool> used(n);
		for (int id : nids)used[id] = true;
		nids.clear();
		for (int id : ids) {
			if (!used[id])nids.push_back(id);
		}
		swap(ids, nids);
	}

	vector<int> locs(vs.size());
	rep(i, vs.size()) {
		ld mi = INF;
		int cj = -1;
		rep(j, vs[i].size()) {
			ld val = pt[vs[i][j]];
			if (p[vs[i][j]].first <= 0 && p[vs[i][j]].second >= 0) {
				//cout << "eeeee "<<val<<"\n";
				val -= 4 * pi;
				//cout << "eeeee " << val << "\n";
			}
			if (val < mi) {
				mi = pt[vs[i][j]];
				//mi = val;
				cj = j;
			}
		}
		//cout << "!? " << cj << "\n";
		rep(j, cj)vs[i].push_back(vs[i][j]);
		vs[i].erase(vs[i].begin(), vs[i].begin() + cj);
		/*cout << "nhello\n";
		rep(j, vs[i].size()) {
			cout << pt[vs[i][j]] << " ";
		}cout << "\n";*/
	}
	/*rep(i, vs.size()) {
		cout << "hello\n";
		coutarray(vs[i]);
	}*/
	int q; cin >> q;
	vector<ld> ans(q, -1);
	vector<LP> qp(q);
	vector<Point> vq(q);
	vector<int> qk(q);
	rep(i, q) {
		int x, y; cin >> x >> y;
		x *= 2; y *= 2;
		qp[i] = { x,y };
		vq[i] = { (ld)x,(ld)y };
		cin >> qk[i];
	}
	vector<ld> qt(q);
	rep(i, q) {
		if (qp[i] == LP{ 0,0 })continue;
		ld t = atan2(qp[i].second, qp[i].first);
		qt[i] = t;
	}
	auto compq = [&](int i, int j) {
		return qt[i] < qt[j];
	};
	vector<int> idq;
	rep(i, q) {
		if (qp[i] == LP{ 0,0 })continue;
		idq.push_back(i);
	}
	sort(all(idq), compq);
	
	//query,input
	auto calc = [&](int i, int j)->ld {
		ll a = (ll)p[j].first * p[j].first + (ll)p[j].second * p[j].second;
		ll b = (ll)p[j].first * qp[i].first + (ll)p[j].second * qp[i].second;
		if (b <= 0)return -1;
		//cout << "? " << i << " " << j << " " << a << " " << b << "\n";
		b *= 2;
		return a / (ld)b;
	};
	rep(i, idq.size()) {
		int id = idq[i];
		//cout << "ee "<<qt[id] << "\n";
		int k = qk[id]; k--;
		vector<ld> vals;
		rep(j, vs.size()) {
			while (true) {
				int id0 = vs[j][locs[j]];
				int id1 = vs[j][(locs[j] + 1) % vs[j].size()];
				ld v0 = calc(id, id0);
				ld v1 = calc(id, id1);
				if (v0 < 0 && v1 < 0) {
					locs[j]++; locs[j] %= vs[j].size();
					if (ccw(vp[id0], vp[id1], Point{0,0}) != 1) {
						 break;
					}
				}
				else if (v0 < 0) {
					locs[j]++; locs[j] %= vs[j].size();
				}
				else if (v1 < 0) {
					break;
				}
				else {
					if (v0 > v1) {
						locs[j]++; locs[j] %= vs[j].size();
					}
					else {
						break;
					}
				}
			}
			int len = min((int)vs[j].size(), 2 * k+1);
			int le = locs[j] - k;
			le %= vs[j].size(); if (le < 0)le += vs[j].size();
			rep(x, len) {
				int loc = (le + x) % vs[j].size();
				ld val = calc(id, vs[j][loc]);
				//cout << "? " << id << " " <<vs[j][loc]<<" "<< val << "\n";
				if(val>0)vals.push_back(val);
			}
		}
		sort(all(vals));
		//cout << "! " << vals.size() << "\n";
		if (vals.size() <= k) {
			ans[id] = -1;
		}
		else {
			ld r = sqrt((ll)qp[id].first * qp[id].first + (ll)qp[id].second * qp[id].second);
			ans[id] = vals[k] * r / 2;
		}
	}
	

	/*rep(i, q) {
		vector<ld> vals;
		ld r = sqrt((ll)qp[i].first * qp[i].first + (ll)qp[i].second * qp[i].second);

		rep(j, n) {
			ld val = calc(i, j);
			val = val * r / 2;
			vals.push_back(val);
		}
		sort(all(vals));
		if (i == 8) {
			coutarray(vals);
		}
	}*/
	rep(i, q) {
		if (ans[i] < 0)cout << -1 << "\n";
		else cout << ans[i] << "\n";
	}
}


signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout << fixed << setprecision(10);
	//init_f();
	//init();
	//while(true)
	//expr();
	//int t; cin >> t; rep(i, t)
	solve();
	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 6ms
memory: 12084kb

input:

5
5 -3
5 4
-6 2
-5 0
4 1
2
-3 -10 1
6 -9 1

output:

8.7002554241
3.2260195623

result:

ok 2 numbers

Test #2:

score: 0
Accepted
time: 10ms
memory: 12252kb

input:

8
4 -1
4 -8
0 9
4 -7
-5 -2
5 -5
7 5
-9 2
10
4 -8 1
7 -7 5
-10 8 2
-9 9 2
4 -7 5
-1 -10 2
6 -3 2
2 -9 3
-10 -10 1
5 9 1

output:

3.1677629681
26.1629509039
5.4614883202
6.3639610307
-1
5.2894082216
3.7267799625
4.6097722286
2.9294423792
4.7617289402

result:

ok 10 numbers

Test #3:

score: 0
Accepted
time: 3ms
memory: 12228kb

input:

5
-4 -7
5 0
2 4
-7 -7
4 4
20
0 -5 2
-4 -7 2
-7 7 3
4 -4 3
-7 4 3
4 -4 1
2 4 1
6 -7 2
4 -4 2
4 4 3
5 4 1
-1 9 2
8 9 3
4 -4 2
6 3 3
-10 -3 2
-7 7 1
9 -4 1
-4 -7 3
-2 0 2

output:

7.0000000000
5.1305276580
-1
-1
-1
3.5355339059
2.2360679775
11.9854077945
15.3206469257
3.5355339059
2.4627400913
4.5276925691
3.7629983059
15.3206469257
2.9814239700
5.6217035048
7.0710678119
2.7357938338
-1
8.1250000000

result:

ok 20 numbers

Test #4:

score: -100
Wrong Answer
time: 3ms
memory: 12112kb

input:

100
63 -48
20 -62
-81 -31
-17 -93
2 -74
72 25
-71 37
-71 17
56 67
-47 65
-89 14
62 30
-71 -33
14 -53
-57 -52
30 80
-14 -69
-45 -19
-54 -71
58 -20
-57 12
5 -56
-76 -2
26 61
24 60
10 -97
-63 38
17 81
-43 -38
44 35
-86 37
62 72
77 11
41 29
14 81
77 55
-54 -33
-43 -51
76 14
55 47
43 24
69 -13
16 75
11 9...

output:

26.7586788688
29.5714059979
24.6221445045
27.7717456547
26.6783667129
24.4237024605
28.8933481964
29.7761695578
36.6609199210
27.2149016024
31.7280950457
27.0711605517
25.2991100306
26.8710651521
28.9958394534
28.3563142462
30.7293082866
25.6496237196
25.1496681332
28.3011569706
28.6117519545
26.690...

result:

wrong answer 9th numbers differ - expected: '31.9403630', found: '36.6609199', error = '0.1477928'