OJ-Problems-Source/HDOJ/1836_autoAC.cpp
2016-08-17 15:13:51 +08:00

209 lines
4.1 KiB
C++

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <map>
#include <vector>
using namespace std;
#define maxn 210
#define LL long long
#define eps 1e-6
#define PI acos(-1.0)
int n,m,tot;
struct Point{
double x,y;
Point(){}
Point(double _x,double _y)
{
x=_x; y=_y;
}
};
bool operator < (const Point& a,const Point& b)
{
if(fabs(a.x-b.x)>eps)
return a.x<b.x;
else if(fabs(a.y-b.y)>eps)
return a.y<b.y;
return false;
}
bool operator==(const Point& a, const Point& b)
{
return fabs(a.x-b.x)<eps&&fabs(a.y-b.y)<eps;
}
struct Line{
Point a,b;
Line(){}
Line(Point _a,Point _b)
{
a=_a; b=_b;
}
};
bool parallel(const Line& ll,const Line& rr)
{
return fabs((ll.a.x-ll.b.x)*(rr.a.y-rr.b.y)-(ll.a.y-ll.b.y)*(rr.a.x-rr.b.x))<eps;
}
Point intesection(const Line& ll, const Line& rr) {
Point ret = ll.a;
double r =
((ll.a.x - rr.a.x) * (rr.a.y - rr.b.y) - (ll.a.y - rr.a.y) * (rr.a.x - rr.b.x)) /
((ll.a.x - ll.b.x) * (rr.a.y - rr.b.y) - (ll.a.y - ll.b.y) * (rr.a.x - rr.b.x));
ret.x += (ll.b.x - ll.a.x) * r;
ret.y += (ll.b.y - ll.a.y) * r;
return ret;
}
struct Edge{
double w;
int v;
bool vis;
Edge(){}
Edge(int _v,double _w,bool _vis=false)
{
v=_v; w=_w; vis=_vis;
}
bool operator <(const Edge& b)const
{
return w<b.w;
}
};
map<Point,int>g;
vector<Point>vp,p[maxn];
Line lines[maxn];
vector<Edge>E[maxn*maxn/2];
vector<double>ans;
Point pts[maxn];
bool check(double a,double b)
{
if(b>a+eps) return b+eps<a+PI;
return b+eps<a-PI;
}
int search(vector<Edge>&E,double w)
{
double d=w+PI;
if(d>PI+eps) d-=2*PI;
int id;
for(id=0;id<E.size();id++)
{
if(fabs(E[id].w-d)<eps)
{
if(id) id--;
else id=E.size()-1;
break;
}
}
return check(E[id].w,d)?id:-1;
}
int sig(double d)
{
return (d>eps) - (d<-eps);
}
double cross(const Point & o, const Point & a, const Point & b)
{
return (a.x-o.x)*(b.y-o.y) - (b.x-o.x)*(a.y-o.y);
}
int inside_convex(Point * ps, int n, Point q)
{
bool s[3] = {1, 1, 1};
ps[n] = ps[0];
for(int i = 0; i < n && (s[0] | s[2]); i ++) {
s[ 1+sig(cross(ps[i+1], q, ps[i])) ] = 0;
}
if(s[0] | s[2]) return s[1]+1;
return 0;
}
void init()
{
int i,j;
for(i=0;i<n;i++)
scanf("%lf %lf",&pts[i].x,&pts[i].y);
g.clear();
vp.clear();
for(i=1;i<=n;i++)
lines[i-1]=Line(pts[i%n],pts[i-1]);
for(i=n;i<n+m;i++)
scanf("%lf %lf %lf %lf",&lines[i].a.x,&lines[i].a.y,&lines[i].b.x,&lines[i].b.y);
for(i=0;i<n+m;i++)
{
p[i].clear();
for(j=0;j<i;j++)
{
if(parallel(lines[i],lines[j])) continue;
Point pt=intesection(lines[i],lines[j]);
g[pt];
p[i].push_back(pt);
p[j].push_back(pt);
}
}
tot=0;
for(map<Point,int>::iterator it=g.begin();it!=g.end();it++)
{
vp.push_back(it->first);
it->second=tot;
E[tot++].clear();
}
for(i=0;i<n+m;i++)
{
if(p[i].size()<2) continue;
sort(p[i].begin(),p[i].end());
p[i].erase(unique(p[i].begin(),p[i].end()),p[i].end());
double ab=atan2(p[i].back().y-p[i].front().y,p[i].back().x-p[i].front().x);
double ba=atan2(p[i].front().y-p[i].back().y,p[i].front().x-p[i].back().x);
for(int j=1;j<p[i].size();j++)
{
int a=g[p[i][j-1]],b=g[p[i][j]];
E[a].push_back(Edge(b,ab));
E[b].push_back(Edge(a,ba));
}
}
for(int i=0;i<tot;i++)
sort(E[i].begin(),E[i].end());
}
void gao()
{
int i,j,s,ans=0;
for(i=0;i<tot;i++)
{
if(!inside_convex(pts,n,vp[i])) continue;
for(j=0;j<E[i].size();j++)
{
if(E[i][j].vis) continue;
int a=i,b=j,c;
E[i][j].vis=true;
double S=vp[a].x*vp[E[i][j].v].y-vp[a].y*vp[E[i][j].v].x;
while(E[a][b].v!=i)
{
c=search(E[E[a][b].v],E[a][b].w);
if(c==-1)
{
S=0; break;
}
a=E[a][b].v,b=c;
if(E[a][b].vis)
{
S=0; break;
}
if(!inside_convex(pts,n,vp[a]))
{
S=0; break;
}
E[a][b].vis=true;
S+=vp[a].x*vp[E[a][b].v].y-vp[a].y*vp[E[a][b].v].x;
}
if(S>2*eps) ans++;
}
}
printf("Number of regions=%d.\n",ans);
}
int main()
{
int ncase;
scanf("%d",&ncase);
while(ncase--)
{
scanf("%d %d",&n,&m);
init();
gao();
}
return 0;
}