POJ2318 TOYS + 2398 Toy Storage

二分+叉积

http://poj.org/problem?id=2318

 http://poj.org/problem?id=2398

//2318
#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
using namespace std;
const double eps=1e-8;
const int maxn=100004;
int dcmp(double x) {
    if(fabs(x) < eps) return 0;
    return x < 0 ? -1 : 1;
}
#define Point Vector
struct Vector{
    double x,y;
    Vector(double x=0,double y=0):x(x),y(y){};
    Vector operator + (const Vector &A) const{
        return Vector(x+A.x,y+A.y);
    }
    Vector operator - (const Vector &A) const{
        return Vector(x-A.x,y-A.y);
    }
    Vector operator * (const double &A) const{
        return Vector(x*A,y*A);
    }
    Vector operator / (const double &A) const{
        return Vector(x/A,y/A);
    }
    bool operator == (const Vector &A) const{
        return dcmp(x-A.x)==0&&dcmp(y-A.y)==0;
    }
};
struct Line{
    Point p1,p2;
    Line(){};
    Line(Point p1,Point p2):p1(p1),p2(p2){}
}li[maxn];
int ans[maxn],n,m;
double U,L,R,D;
double PolarAngle(Vector A){
    return atan2(A.y,A.x);
}
Vector rotate(Vector &A,double a){
    return A=Vector(A.x*cos(a)-A.y*sin(a),A.x*sin(a)+A.y*cos(a));
}
double Dot(Vector A,Vector B){
    return A.x*B.x+A.y*B.y;
}
double Cross(Vector A,Vector B){
    return A.x*B.y-A.y*B.x;
}
bool pointisleft(Point p,Line line)
{
    Vector v1=line.p1-p;
    Vector v2=line.p2-p;
    return dcmp(Cross(v1,v2))<0;
}
int main(){
    while(scanf("%d",&n)!=EOF){
        if(n==0) return 0;
        scanf("%d",&m);
        scanf("%lf%lf%lf%lf",&L,&U,&R,&D);
        //Point p1=Point(L,U);
        //Point p2=Point(R,D);
        //li[0]=Line(p1,p2);
        for(int i=0;i<n;i++){
            double x1,x2;
            scanf("%lf%lf",&x1,&x2);
            Point p1=Point(x1,U);
            Point p2=Point(x2,D);
            li[i]=Line(p1,p2);
        }
        memset(ans,0,sizeof(ans)); 
        for(int i=1;i<=m;i++){
            Point p;scanf("%lf%lf",&p.x,&p.y);
            int l=0,r=n-1;
            while(l<=r){
                int mid=l+r>>1;
                if(Cross(li[mid].p1-li[mid].p2,p-li[mid].p2)>0) r=mid-1;
                //if(pointisleft(p,li[mid])) r=mid-1;//两种写法
                else l=mid+1;
            }
            ans[l]++;
        }
        for(int i=0;i<=n;i++){
            printf("%d: %d
",i,ans[i]);
        }
        printf("
");
    }
}

//2398
#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
using namespace std;
const double eps=1e-8;
const int maxn=100004;
int dcmp(double x) {
    if(fabs(x) < eps) return 0;
    return x < 0 ? -1 : 1;
}
#define Point Vector
struct Vector{
    double x,y;
    Vector(double x=0,double y=0):x(x),y(y){};
    Vector operator + (const Vector &A) const{
        return Vector(x+A.x,y+A.y);
    }
    Vector operator - (const Vector &A) const{
        return Vector(x-A.x,y-A.y);
    }
    Vector operator * (const double &A) const{
        return Vector(x*A,y*A);
    }
    Vector operator / (const double &A) const{
        return Vector(x/A,y/A);
    }
    bool operator == (const Vector &A) const{
        return dcmp(x-A.x)==0&&dcmp(y-A.y)==0;
    }
};
struct Line{
    Point p1,p2;
    Line(){};
    Line(Point p1,Point p2):p1(p1),p2(p2){}
}li[maxn];
bool operator < (Line l1,Line l2){
    if(l1.p1.x==l2.p1.x) return l1.p1.y<l2.p1.y;
    else return l1.p1.x<l2.p1.x;
}
int ans[maxn],num[maxn],n,m;
double U,L,R,D;
double PolarAngle(Vector A){
    return atan2(A.y,A.x);
}
Vector rotate(Vector &A,double a){
    return A=Vector(A.x*cos(a)-A.y*sin(a),A.x*sin(a)+A.y*cos(a));
}
double Dot(Vector A,Vector B){
    return A.x*B.x+A.y*B.y;
}
double Cross(Vector A,Vector B){
    return A.x*B.y-A.y*B.x;
}
bool pointisleft(Point p,Line line)
{
    Vector v1=  line.p1-p;
    Vector v2=  line.p2-p;
    //cout<<line.p1.x<<' '<<line.p1.y<<' '<<line.p2.x<<' '<<line.p2.y<<' '<<p.x<<' '<<p.y<<endl;
    //cout<<v1.x<<' '<<v1.y<<' '<<v2.x<<' '<<v2.y<<endl;
    //cout<<Cross(v1,v2)<<endl;
    return dcmp(Cross(v1,v2))<0;
}
int main(){
    while(scanf("%d",&n)!=EOF){
        if(n==0) return 0;
        scanf("%d",&m);
        scanf("%lf%lf%lf%lf",&L,&U,&R,&D);
        //Point p1=Point(L,U);
        //Point p2=Point(R,D);
        //li[0]=Line(p1,p2);
        for(int i=0;i<n;i++){
            double x1,x2;
            scanf("%lf%lf",&x1,&x2);
            Point p1=Point(x1,U);
            Point p2=Point(x2,D);
            li[i]=Line(p1,p2);
        }
        sort(li,li+n);
        memset(ans,0,sizeof(ans)); 
        memset(num,0,sizeof(num)); 
        for(int i=1;i<=m;i++){
            Point p;scanf("%lf%lf",&p.x,&p.y);
            int l=0,r=n-1;
            while(l<=r){
                int mid=l+r>>1;
                if(Cross(li[mid].p1-li[mid].p2,p-li[mid].p2)>0) r=mid-1;
                //cout<<pointisleft(p,li[mid])<<endl;
                //if(pointisleft(p,li[mid])) r=mid-1;
                else l=mid+1;
            }
            ans[l]++;
        }
        for(int i=0;i<=n;i++){
            num[ans[i]]++;
        }
        printf("Box
");
        for(int i=1;i<=m;i++){
            if(num[i]) 
            printf("%d: %d
",i,num[i]);
        }
        //printf("
");
    }
}