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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 Sky | bulijiojiodibuliduo# | WA | 1ms | 4164kb | C++17 | 12.2kb | 2023-09-27 02:55:18 | 2023-09-27 02:55:19 |
Judging History
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