http://www.lydsy.com/JudgeOnline/problem.php?id=1199
求出圆x的范围
把要判断的点按x从小到大排序
枚举图形
二分出x满足这个图形的一段区间
枚举这段区间内的每个点
圆判断到圆心的距离
矩形判断y
代码不是我的~~~
#include<bits/stdc++.h> #define N 1000010 using namespace std; const double eps=1e-7; struct node { double x1,x2,y1,y2; double x,y,r; char c; bool friend operator < (node a,node b) { return a.x1<b.x1; } }a[N]; char s[3]; int out[N]; struct point { double x,y; int num; }e[N]; int n,m; double sqr(double x) { return x*x; } bool pd(double x1,double y1,double x,double y,double r) { return sqr(x-x1)+sqr(y-y1)<sqr(r); } bool cmp(point a,point b) { return a.x<b.x; } int main() { scanf("%d%d",&n,&m); for(int i=1;i<=n;i++) { scanf("%s",s+1); if(s[1]==‘r‘) { scanf("%lf%lf%lf%lf",&a[i].x1,&a[i].y1,&a[i].x2,&a[i].y2); if(a[i].x1>a[i].x2) swap(a[i].x1,a[i].x2),swap(a[i].y1,a[i].y2); a[i].c=s[1]; } else { scanf("%lf%lf%lf",&a[i].x,&a[i].y,&a[i].r); a[i].x1=a[i].x-a[i].r;a[i].x2=a[i].x+a[i].r; a[i].c=s[1]; } } for(int i=1;i<=m;i++) scanf("%lf%lf",&e[i].x,&e[i].y),e[i].num=i; sort(e+1,e+m+1,cmp); for(int i=1;i<=n;i++) { int ll=-1,rr=-1; int l=1,r=m; while(l<=r) { int mid=l+r>>1; if(e[mid].x>a[i].x1) { ll=mid; r=mid-1; } else l=mid+1; } l=1,r=m; while(l<=r) { int mid=l+r>>1; if(e[mid].x<a[i].x2) { rr=mid; l=mid+1; } else r=mid-1; } if(ll==-1 || rr==-1) continue; for(int j=ll;j<=rr;j++) { if(a[i].c==‘c‘) { if(pd(e[j].x,e[j].y,a[i].x,a[i].y,a[i].r)) out[e[j].num]++; } else { if(e[j].y<a[i].y2&&e[j].y>a[i].y1) out[e[j].num]++; } } } for(int i=1;i<=m;i++) cout<<out[i]<<"\n"; return 0; }