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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#189241#5106. Islands from the Skybulijiojiodibuliduo#WA 1ms4164kbC++1712.2kb2023-09-27 02:55:182023-09-27 02:55:19

Judging History

你现在查看的是最新测评结果

  • [2023-09-27 02:55:19]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:4164kb
  • [2023-09-27 02:55:18]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> BI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}()); 
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

typedef double db;
const db EPS = 1e-9;
const db PI = acos(-1.0);
  
inline int sign(db a) { return a < -EPS ? -1 : a > EPS; }
  
inline int cmp(db a, db b){ return sign(a-b); }
  
struct P {
	db x, y;
	P() {}
	P(db _x, db _y) : x(_x), y(_y) {}
	P operator+(P p) { return {x + p.x, y + p.y}; }
	P operator-(P p) { return {x - p.x, y - p.y}; }
	P operator*(db d) { return {x * d, y * d}; }
	P operator/(db d) { return {x / d, y / d}; }
 
	bool operator<(P p) const { 
		int c = cmp(x, p.x);
		if (c) return c == -1;
		return cmp(y, p.y) == -1;
	}
 
	bool operator==(P o) const{
		return cmp(x,o.x) == 0 && cmp(y,o.y) == 0;
	}
 
	db dot(P p) { return x * p.x + y * p.y; }
	db det(P p) { return x * p.y - y * p.x; }
	 
	db distTo(P p) { return (*this-p).abs(); }
	db alpha() { return atan2(y, x); }
	void read() { cin>>x>>y; }
	void write() {cout<<"("<<x<<","<<y<<")"<<endl;}
	db abs() { return sqrt(abs2());}
	db abs2() { return x * x + y * y; }
	P rot90() { return P(-y,x);}
	P unit() { return *this/abs(); }
	int quad() const { return sign(y) == 1 || (sign(y) == 0 && sign(x) >= 0); }
	P rot(db an){ return {x*cos(an)-y*sin(an),x*sin(an) + y*cos(an)}; }
};
  
struct L{ //ps[0] -> ps[1]
	P ps[2];
	P dir_;
	P& operator[](int i) { return ps[i]; }
	P dir() { return dir_; }
	L (P a,P b) {
		ps[0]=a;
		ps[1]=b;
		dir_ = (ps[1]-ps[0]).unit();
	}
	bool include(P p) { return sign((dir_).det(p - ps[0])) > 0; }
	L push(){ // push eps outward
		const double eps = 1e-8;
		P delta = (ps[1] - ps[0]).rot90().unit() * eps;
		return {ps[0] + delta, ps[1] + delta};
	}
};

#define cross(p1,p2,p3) ((p2.x-p1.x)*(p3.y-p1.y)-(p3.x-p1.x)*(p2.y-p1.y))
#define crossOp(p1,p2,p3) sign(cross(p1,p2,p3))
  
bool chkLL(P p1, P p2, P q1, P q2) {
	db a1 = cross(q1, q2, p1), a2 = -cross(q1, q2, p2);
	return sign(a1+a2) != 0;
}
 
P isLL(P p1, P p2, P q1, P q2) {
	db a1 = cross(q1, q2, p1), a2 = -cross(q1, q2, p2);
	return (p1 * a2 + p2 * a1) / (a1 + a2);
}
  
P isLL(L l1,L l2){ return isLL(l1[0],l1[1],l2[0],l2[1]); }
  
bool intersect(db l1,db r1,db l2,db r2){
	if(l1>r1) swap(l1,r1); if(l2>r2) swap(l2,r2); 
	return !( cmp(r1,l2) == -1 || cmp(r2,l1) == -1 );
}
  
bool isSS(P p1, P p2, P q1, P q2){
	return intersect(p1.x,p2.x,q1.x,q2.x) && intersect(p1.y,p2.y,q1.y,q2.y) && 
	crossOp(p1,p2,q1) * crossOp(p1,p2,q2) <= 0 && crossOp(q1,q2,p1)
			* crossOp(q1,q2,p2) <= 0;
}
  
bool isSS_strict(P p1, P p2, P q1, P q2){
	return crossOp(p1,p2,q1) * crossOp(p1,p2,q2) < 0 && crossOp(q1,q2,p1)
			* crossOp(q1,q2,p2) < 0;
}
  
bool isMiddle(db a, db m, db b) {
	return sign(a - m) == 0 || sign(b - m) == 0 || (a < m != b < m);
}
  
bool isMiddle(P a, P m, P b) {
	return isMiddle(a.x, m.x, b.x) && isMiddle(a.y, m.y, b.y);
}
  
bool onSeg(P p1, P p2, P q){
	return crossOp(p1,p2,q) == 0 && isMiddle(p1, q, p2);
}
 
bool onSeg_strict(P p1, P p2, P q){
	return crossOp(p1,p2,q) == 0 && sign((q-p1).dot(p1-p2)) * sign((q-p2).dot(p1-p2)) < 0;
}
  
P proj(P p1, P p2, P q) {
	P dir = p2 - p1;
	return p1 + dir * (dir.dot(q - p1) / dir.abs2());
}
  
P reflect(P p1, P p2, P q){
	return proj(p1,p2,q) * 2 - q;
}
  
db nearest(P p1,P p2,P q){
	if (p1==p2) return p1.distTo(q);
	P h = proj(p1,p2,q);
	if(isMiddle(p1,h,p2))
		return q.distTo(h);
	return min(p1.distTo(q),p2.distTo(q));
}
  
db disSS(P p1, P p2, P q1, P q2){
	if(isSS(p1,p2,q1,q2)) return 0;
	return min(min(nearest(p1,p2,q1),nearest(p1,p2,q2)), min(nearest(q1,q2,p1),nearest(q1,q2,p2)));
}
  
db rad(P p1,P p2){
	return atan2l(p1.det(p2),p1.dot(p2));
}
  
db incircle(P p1, P p2, P p3){
	db A = p1.distTo(p2);
	db B = p2.distTo(p3);
	db C = p3.distTo(p1);
	return sqrtl(A*B*C/(A+B+C));
}
  
//polygon
  
db area(vector<P> ps){
	db ret = 0; rep(i,0,ps.size()) ret += ps[i].det(ps[(i+1)%ps.size()]); 
	return ret/2;
}
  
int contain(vector<P> ps, P p){ //2:inside,1:on_seg,0:outside
	int n = ps.size(), ret = 0; 
	rep(i,0,n){
		P u=ps[i],v=ps[(i+1)%n];
		if(onSeg(u,v,p)) return 1;
		if(cmp(u.y,v.y)<=0) swap(u,v);
		if(cmp(p.y,u.y) >0 || cmp(p.y,v.y) <= 0) continue;
		ret ^= crossOp(p,u,v) > 0;
	}
	return ret*2;
}
  
vector<P> convexHull(vector<P> ps) {
	int n = ps.size(); if(n <= 1) return ps;
	sort(ps.begin(), ps.end());
	vector<P> qs(n * 2); int k = 0;
	for (int i = 0; i < n; qs[k++] = ps[i++]) 
		while (k > 1 && crossOp(qs[k - 2], qs[k - 1], ps[i]) <= 0) --k;
	for (int i = n - 2, t = k; i >= 0; qs[k++] = ps[i--])
		while (k > t && crossOp(qs[k - 2], qs[k - 1], ps[i]) <= 0) --k;
	qs.resize(k - 1);
	return qs;
}
  
vector<P> convexHullNonStrict(vector<P> ps) {
	//caution: need to unique the Ps first
	int n = ps.size(); if(n <= 1) return ps;
	sort(ps.begin(), ps.end());
	vector<P> qs(n * 2); int k = 0;
	for (int i = 0; i < n; qs[k++] = ps[i++]) 
		while (k > 1 && crossOp(qs[k - 2], qs[k - 1], ps[i]) < 0) --k;
	for (int i = n - 2, t = k; i >= 0; qs[k++] = ps[i--])
		while (k > t && crossOp(qs[k - 2], qs[k - 1], ps[i]) < 0) --k;
	qs.resize(k - 1);
	return qs;
}
  
db convexDiameter(vector<P> ps){
	int n = ps.size(); if(n <= 1) return 0;
	int is = 0, js = 0; rep(k,1,n) is = ps[k]<ps[is]?k:is, js = ps[js] < ps[k]?k:js;
	int i = is, j = js;
	db ret = ps[i].distTo(ps[j]);
	do{
		if((ps[(i+1)%n]-ps[i]).det(ps[(j+1)%n]-ps[j]) >= 0)
			(++j)%=n;
		else
			(++i)%=n;
		ret = max(ret,ps[i].distTo(ps[j]));
	}while(i!=is || j!=js);
	return ret;
}
  
vector<P> convexCut(const vector<P>&ps, P q1, P q2) {
	vector<P> qs;
	int n = ps.size();
	rep(i,0,n){
		P p1 = ps[i], p2 = ps[(i+1)%n];
		int d1 = crossOp(q1,q2,p1), d2 = crossOp(q1,q2,p2);
		if(d1 >= 0) qs.pb(p1);
		if(d1 * d2 < 0) qs.pb(isLL(p1,p2,q1,q2));
	}
	return qs;
}
  
//min_dist
  
db min_dist(vector<P>&ps,int l,int r){
	if(r-l<=5){
		db ret = 1e100;
		rep(i,l,r) rep(j,l,i) ret = min(ret,ps[i].distTo(ps[j]));
		return ret;
	}
	int m = (l+r)>>1;
	db ret = min(min_dist(ps,l,m),min_dist(ps,m,r));
	vector<P> qs; rep(i,l,r) if(abs(ps[i].x-ps[m].x)<= ret) qs.pb(ps[i]);
	sort(qs.begin(), qs.end(),[](P a,P b) -> bool {return a.y<b.y; });
	rep(i,1,qs.size()) for(int j=i-1;j>=0&&qs[j].y>=qs[i].y-ret;--j)
		ret = min(ret,qs[i].distTo(qs[j]));
	return ret;
}
  
int type(P o1,db r1,P o2,db r2){
	db d = o1.distTo(o2);
	if(cmp(d,r1+r2) == 1) return 4;
	if(cmp(d,r1+r2) == 0) return 3;
	if(cmp(d,abs(r1-r2)) == 1) return 2;
	if(cmp(d,abs(r1-r2)) == 0) return 1;
	return 0;
}
  
vector<P> isCL(P o,db r,P p1,P p2){
	if (cmp(abs((o-p1).det(p2-p1)/p1.distTo(p2)),r)>0) return {};
	db x = (p1-o).dot(p2-p1), y = (p2-p1).abs2(), d = x * x - y * ((p1-o).abs2() - r*r);
	d = max(d,(db)0.0); P m = p1 - (p2-p1)*(x/y), dr = (p2-p1)*(sqrt(d)/y);
	return {m-dr,m+dr}; //along dir: p1->p2
}
  
vector<P> isCC(P o1, db r1, P o2, db r2) { //need to check whether two circles are the same
	db d = o1.distTo(o2); 
	if (cmp(d, r1 + r2) == 1) return {};
	if (cmp(d,abs(r1-r2))==-1) return {};
	d = min(d, r1 + r2);
	db y = (r1 * r1 + d * d - r2 * r2) / (2 * d), x = sqrt(r1 * r1 - y * y);
	P dr = (o2 - o1).unit();
	P q1 = o1 + dr * y, q2 = dr.rot90() * x;
	return {q1-q2,q1+q2};//along circle 1
}
  
vector<P> tanCP(P o, db r, P p) {
	db x = (p - o).abs2(), d = x - r * r;
	if (sign(d) <= 0) return {}; // on circle => no tangent
	P q1 = o + (p - o) * (r * r / x);
	P q2 = (p - o).rot90() * (r * sqrt(d) / x);
	return {q1-q2,q1+q2}; //counter clock-wise
}
  
// extanCC, intanCC : -r2, tanCP : r2 = 0
vector<pair<P, P>> tanCC(P o1, db r1, P o2, db r2) {
	P d = o2 - o1;
	db dr = r1 - r2, d2 = d.abs2(), h2 = d2 - dr * dr;
	if (sign(d2) == 0|| sign(h2) < 0) return {};
	h2 = max(0.0, h2);
	vector<pair<P, P>> ret;
	for (db sign : {-1, 1}) {
		P v = (d * dr + d.rot90() * sqrt(h2) * sign) / d2;
		ret.push_back({o1 + v * r1, o2 + v * r2});
	}
	if (sign(h2) == 0) ret.pop_back();
	return ret;
}
  
db areaCT(db r, P p1, P p2){
	vector<P> is = isCL(P(0,0),r,p1,p2);
	if(is.empty()) return r*r*rad(p1,p2)/2;
	bool b1 = cmp(p1.abs2(),r*r) == 1, b2 = cmp(p2.abs2(), r*r) == 1;
	if(b1 && b2){
		P md=(is[0]+is[1])/2;
		if(sign((p1-md).dot(p2-md)) <= 0) 
			return r*r*(rad(p1,is[0]) + rad(is[1],p2))/2 + is[0].det(is[1])/2;
		else return r*r*rad(p1,p2)/2;
	}
	if(b1) return (r*r*rad(p1,is[0]) + is[0].det(p2))/2;
	if(b2) return (p1.det(is[1]) + r*r*rad(is[1],p2))/2;
	return p1.det(p2)/2;
}
  
bool parallel(L l0, L l1) { return sign( l0.dir().det( l1.dir() ) ) == 0; }
  
bool sameDir(L l0, L l1) { return parallel(l0, l1) && sign(l0.dir().dot(l1.dir()) ) == 1; }
  
bool cmp (P a,  P b) {
	if (a.quad() != b.quad()) {
		return a.quad() < b.quad();
	} else {
		return sign( a.det(b) ) > 0;
	}
}
  
bool operator < (L l0, L l1) {
	if (sameDir(l0, l1)) {
		return l1.include(l0[0]);
	} else {
		return cmp( l0.dir(), l1.dir() );
	}
}
  
bool check(L u, L v, L w) { 
	return w.include(isLL(u,v)); 
}
  
vector<P> halfPlaneIS(vector<L> &l) {
	sort(l.begin(), l.end());
	deque<L> q;
	for (int i = 0; i < (int)l.size(); ++i) {
		if (i && sameDir(l[i], l[i - 1])) continue;
		while (q.size() > 1 && !check(q[q.size() - 2], q[q.size() - 1], l[i])) q.pop_back();
		while (q.size() > 1 && !check(q[1], q[0], l[i])) q.pop_front();
		q.push_back(l[i]);
	}
	while (q.size() > 2 && !check(q[q.size() - 2], q[q.size() - 1], q[0])) q.pop_back();
	while (q.size() > 2 && !check(q[1], q[0], q[q.size() - 1])) q.pop_front();
	vector<P> ret;
	for (int i = 0; i < (int)q.size(); ++i) ret.push_back(isLL(q[i], q[(i + 1) % q.size()]));
	return ret;
}
 
P inCenter(P A, P B, P C) {
	double a = (B - C).abs(), b = (C - A).abs(), c = (A - B).abs();
	return (A * a + B * b + C * c) / (a + b + c);
}
 
P circumCenter(P a, P b, P c) { 
	P bb = b - a, cc = c - a;
	double db = bb.abs2(), dc = cc.abs2(), d = 2 * bb.det(cc);
	return a - P(bb.y * dc - cc.y * db, cc.x * db - bb.x * dc) / d;
}
 
P othroCenter(P a, P b, P c) { 
	P ba = b - a, ca = c - a, bc = b - c;
	double Y = ba.y * ca.y * bc.y,
	A = ca.x * ba.y - ba.x * ca.y,
	x0 = (Y + ca.x * ba.y * b.x - ba.x * ca.y * c.x) / A,
	y0 = -ba.x * (x0 - c.x) / ba.y + ca.y;
	return {x0, y0};
}


const int N=111;
int n,m;
vector<pair<P,P>> seg;
P p[N],p1[N],p2[N],dir[N];
int pz[N],qz[N];
int main() {
	scanf("%d%d",&n,&m);
	rep(i,0,n) {
		int n0;
		scanf("%d",&n0);
		rep(j,0,n0) {
			int x,y;
			scanf("%d%d",&x,&y);
			p[j]=P(x,y);
		}
		rep(j,0,n0) seg.pb(mp(p[j],p[(j+1)%n0]));
	}
	shuffle(all(seg),mrand);
	rep(i,0,m) {
		int px,py,qx,qy;
		scanf("%d%d%d%d%d%d",&px,&py,&pz[i],
			&qx,&qy,&qz[i]);
		p1[i]=P(px,py);
		p2[i]=P(qx,qy);
		dir[i]=(p2[i]-p1[i]).unit().rot90();
	}
	auto check=[&](db ang,P px,P py) {
		P dx=(py-px).unit();
		vector<pair<db,db>> seg;
		seg.pb(mp(0,0));
		db len=(py-px).abs();
		seg.pb(mp(len,len));
		rep(i,0,m) {
			vector<P> reg{p1[i]-dir[i]*pz[i]*tan(ang),
				p2[i]-dir[i]*qz[i]*tan(ang),p2[i]+dir[i]*qz[i]*tan(ang),
				p1[i]+dir[i]*pz[i]*tan(ang)};
			vector<P> r{px,py};
			rep(j,0,4) r=convexCut(r,reg[j],reg[(j+1)%4]);
			if (SZ(r)>=2) {
				db sl=(r[0]-px).dot(dx);
				db sr=(r[1]-px).dot(dx);
				if (sl>sr) swap(sl,sr);
				seg.pb(mp(sl,sr));
			}
		}
		sort(all(seg));
		db pmx=0;
		rep(i,0,SZ(seg)) {
			if (cmp(seg[i].fi,pmx)==1) return false;
			pmx=max(pmx,seg[i].se);
		}
		return true;
	};
	db ans=0;
	for (auto [p1,p2]:seg) {
		if (!check(ans,p1,p2)) {
			db L=ans,R=PI/2;
			rep(i,0,100) {
				db md=(L+R)*0.5;
				if (!check(md,p1,p2)) L=md; else R=md;
				if (cmp(L,PI/2)>=0) {
					puts("impossible");
					return 0;
				}
			}
			ans=L;
		}
	}
	printf("%.10f\n",ans/PI*180);
}

詳細信息

Test #1:

score: 100
Accepted
time: 1ms
memory: 4068kb

input:

1 1
3
-5 0
5 0
0 5
-10 10 10 10 10 10

output:

44.9999999999

result:

ok 

Test #2:

score: 0
Accepted
time: 1ms
memory: 4028kb

input:

1 1
3
-5 0
5 0
0 5
-10 0 10 10 0 10

output:

26.5650511738

result:

ok 

Test #3:

score: 0
Accepted
time: 1ms
memory: 4164kb

input:

1 1
3
-5 0
5 0
0 5
0 10 10 10 0 10

output:

46.6861433398

result:

ok 

Test #4:

score: 0
Accepted
time: 1ms
memory: 4156kb

input:

1 1
3
-5 0
5 0
0 5
0 10 5 10 0 10

output:

59.4910411314

result:

ok 

Test #5:

score: 0
Accepted
time: 1ms
memory: 4060kb

input:

1 1
3
-5 0
5 0
0 5
0 10 20 -10 0 10

output:

31.2196984464

result:

ok 

Test #6:

score: -100
Wrong Answer
time: 1ms
memory: 3932kb

input:

1 3
3
-5 0
5 0
0 5
-10 0 25 10 0 20
-5 10 10 10 -5 20
-4 1 100 5 10 100

output:

0.0000000000

result:

wrong answer