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| #include <algorithm> #include <vector>
template<typename T> struct Point{ T x,y; Point(T x=0,T y=0):x(x),y(y){} Point operator+(const Point& o) const{return Point(x+o.x,y+o.y);} Point operator-(const Point& o) const{return Point(x-o.x,y-o.y);} bool operator==(const Point& o) const{return x==o.x&&y==o.y;} T operator*(const Point& o) const{return x*o.x+y*o.y;} T operator^(const Point& o) const{return x*o.y-y*o.x;} bool operator<(const Point& o) const{ if(x==o.x){ return y<o.y; } return x<o.x; } };
template<typename T> vector<Point<T>> convexHull(vector<Point<T>> pts){ int n=pts.size(); sort(pts.begin(),pts.end()); if(n<=2){ return pts; }
vector<Point<T>> hull; for(auto& p:pts){ while(hull.size()>=2&&((hull.back()-hull[hull.size()-2])^(p-hull.back()))<=0){ hull.pop_back(); } hull.push_back(p); }
size_t lwr=hull.size(); for(int i=pts.size()-2;i>=0;i--){ Point<T> p=pts[i]; while(hull.size()>lwr&&((hull.back()-hull[hull.size()-2])^(p-hull.back()))<=0){ hull.pop_back(); } hull.push_back(p); }
if(hull.size()>1){ hull.pop_back(); } return hull; }
template<typename T> vector<Point<T>> standardize(const vector<Point<T>>& poly){ if(poly.empty()){ return poly; }
int idx=0; for(int i=1;i<(int)poly.size();i++){ if(poly[i].y<poly[idx].y||(poly[i].y==poly[idx].y&&poly[i].x<poly[idx].x)){ idx = i; } }
vector<Point<T>> ret; for(int i=idx;i<(int)poly.size();i++){ ret.push_back(poly[i]); } for(int i=0;i<idx;i++){ ret.push_back(poly[i]); } return ret; }
template<typename T> vector<Point<T>> minkowskiSum(const vector<Point<T>>& a,const vector<Point<T>>& b){ vector<Point<T>> polyA=standardize(a),polyB=standardize(b); int n=polyA.size(),m=polyB.size(); vector<Point<T>> edA,edB; for(int i=0;i<n;i++){ edA.push_back(polyA[(i+1)%n]-polyA[i]); } for(int i=0;i<m;i++){ edB.push_back(polyB[(i+1)%m]-polyB[i]); }
vector<Point<T>> merged; int i=0,j=0; while(i<n&&j<m){ ll cr=edA[i]^edB[j]; if(cr>0){ merged.push_back(edA[i]); i++; } else if(cr<0){ merged.push_back(edB[j]); j++; } else{ Point<T> sum=edA[i]+edB[j]; if(sum.x!=0||sum.y!=0){ merged.push_back(sum); } i++; j++; } }
while(i<n){ merged.push_back(edA[i]); i++; } while(j<m){ merged.push_back(edB[j]); j++; }
Point<T> cur=polyA[0]+polyB[0]; vector<Point<T>> c={cur}; for(auto& pt:merged){ cur = cur+pt; c.push_back(cur); } if(c.size()>1&&c.back()==c[0]){ c.pop_back(); } return c; }
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