CodeforcesRound#113(Div.2)B判断多边形是否在凸包内

int cmp(double x){
 if(fabs(x) < 1e-8) return 0 ;
 return x > 0 ? 1 : -1 ;
}

struct point{
 double x , y ;
 int k ;
 point(){}
 point(double _x , double _y):x(_x) , y(_y){}
 point operator - (const point &o){
 return point(x - o.x , y - o.y) ;
 }
 friend double operator ^ (const point &a , const point &b){
 return a.x * b.y - a.y * b.x ;
 }
 friend bool operator < (const point &a , const point &b){
 if(cmp(a.x - b.x) != 0) return cmp(a.x - b.x) < 0 ;
 if(cmp(a.y - b.y) != 0) return cmp(a.y - b.y) < 0 ;
 return a.k < b.k ;
 }
 friend bool operator == (const point &a , const point &b){
 return cmp(a.x - b.x) == 0 && cmp(a.y - b.y) == 0 ;
 }
};

vector convex_hull(vector a){
 vector s(a.size() * 2 + 5) ;
 sort(a.begin() , a.end()) ;
 int m = 0 ;
 for(int i = 0 ; i < a.size() ; i++){
 while(m > 1 && cmp((s[m-1] - s[m-2]) ^ (a[i] - s[m-2])) < 0) m-- ;
 s[m++] = a[i] ;
 }
 int k = m ;
 for(int i = a.size() - 2 ; i >= 0 ; i--){
 while(m > k && cmp((s[m-1] - s[m-2]) ^ (a[i] - s[m-2])) < 0) m-- ;
 s[m++] = a[i] ;
 }
 s.resize(m) ;
 if(a.size() > 1) s.resize(m-1) ;
 return s ;
}

int main(){
 int i , n , m , ans = 0 ;
 vector lis(200000) ;
 cin>>n;
 for(i = 0 ; i < n ; i++){
 scanf("%lf%lf" , &lis[i].x , &lis[i].y) ;
 lis[i].k = 0 ;
 }
 cin>>m ;
 for(i = 0 ; i < m ; i++){
 scanf("%lf%lf" , &lis[n+i].x , &lis[n+i].y) ;
 lis[n+i].k = 1 ;
 }
 lis.resize(n + m) ;
 vector hull = convex_hull(lis) ;
 for(i = 0 ; i < hull.size() ; i++){
 if(hull[i].k){
 ans = 1 ;
 break ;
 }
 }
 printf("%s\n" , ans ? "NO" : "YES") ;
 return 0 ;
}