#include #include using namespace std; struct P{ double x,y; }; double len(P a, P b){ return sqrt(pow(a.x-b.x,2)+pow(a.y-b.y,2)); } double deg(P a, P b, P c){ return acos(((b.x-a.x)*(c.x-a.x)+(b.y-a.y)*(c.y-a.y))/(sqrt(pow(b.x-a.x,2)+pow(b.y-a.y,2))*sqrt(pow(c.x-a.x,2)+pow(c.y-a.y,2)))); } bool isParallel(P a, P b, P c, P d){ try { if ((b.x==a.x && c.x==d.x)||(b.y==a.y && c.y==d.y)) return true; if ((b.y-a.y)/(b.x-a.x) == (d.y-c.y)/(d.x-c.x)) return true; else return false; } catch(...){ return false; } } int main() { P p1={-1,0},p2={1,2},p3={2,1},p4={0,-1};//rectangle //P p1={-1,0},p2={0,2},p3={1,0},p4={0,-2};//rhombus //P p1={0,1},p2={1,2},p3={2,1},p4={1,0};//square //P p1={0,0},p2={0,2},p3={3,3},p4={2,0};//kite //P p1={0,0},p2={1,1},p3={2,0},p4={1,-10};//kite //P p1={0,0},p2={1,3},p3={3,3},p4={10,0};//trapezium //P p1={0,0},p2={3,3},p3={5,3},p4={8,0};//i trapezium //P p1={0,0},p2={2,2},p3={3,1},p4={3,0};//quadrilateral double AB,BC,CD,DA,a,b,c,d; AB=len(p1, p2); BC=len(p2, p3); CD=len(p3, p4); DA=len(p4, p1); a=deg(p1,p2,p4); b=deg(p2,p3,p1); c=deg(p3,p4,p2); d=deg(p4,p1,p3); if (AB==BC && BC==CD && CD==DA && a==b && b==c && c==d) cout << "SQUARE"; else if (AB==CD && BC==DA && a==b && b==c && c==d) cout << "RECTANGLE"; else if (AB==BC && BC==CD && CD==DA && a==c && b==d) cout << "RHOMBUS"; else if (AB==CD && BC==DA && a==c && b==d) cout << "PARALLELOGRAM"; else if ((AB==DA && CD==BC && b==d)||(AB==BC && CD==DA && a==c)) cout << "KITE"; else if (isParallel(p1,p2,p3,p4) || isParallel(p2,p3,p4,p1)) { if (a+c==b+d) cout << "ISOSCELES TRAPEZIUM"; else cout << "TRAPEZIUM"; } else cout << "QUADRILATERAL"; return 0; }

Types of quadrilateral