uva–10652 Board wrapping[Convex bag]

Test instructions

Gives the midpoint, length, width and clockwise angle of n rectangles. Lets you wrap them up with the smallest convex polygon to calculate the percentage of the rectangular area that occupies the convex polygon.

With the algorithm of convex hull given by large petition, each vertex of the rectangle is convex and the area of convex hull is calculated.

#include"bits/stdc++.h"using namespacestd;Const intMAXN = the;Const Doubleeps=1e-8;Const DoublePI = ACOs (-1.0);structPoint {Doublex, y; Point (Doublex =0.0,Doubley =0.0): X (x), Y (y) {}};typedef point Vector; Pointoperator+(Point A, point B) {returnPoint (a.x+b.x, a.y+b.y);} Pointoperator-(Point A, point B) {returnPoint (a.x-b.x, a.y-b.y);} Pointoperator* (Point A,Doublep) {returnPoint (A.x*p, a.y*p);} Pointoperator/(Point A,Doublep) {returnPoint (a.x/p, a.y/p);}BOOL operator< (Constpoint& A,Constpoint&b) {returna.x<b.x | | (a.x==b.x && a.y<b.y);}intDCMP (Doublex) {if(Fabs (x) <eps)return 0;returnx<0?-1:1;}BOOL operator== (Constpoint& A,ConstPoint &b) {returnDCMP (a.x-b.x) = =0&& dcmp (a.y-b.y) = =0;}DoubleDot A, point B) {returna.x*b.x+a.y*b.y;}DoubleCross (Point A, point B) {returna.x*b.y-a.y*b.x;}DoubleLength (Point A) {returnsqrt (Dot (a,a));} Vector Normal (vector A) {returnVector (-A.Y, a.x)/Length (A);}DoubleAngle (vector A, vector B) {returnACOs (Dot (b)/length (A)/Length (B)); Vector Rotate (vector A,Doublerad) {    returnVector (A.x*cos (RAD)-a.y*sin (RAD), A.x*sin (RAD) +a.y*cos (RAD));} DoublePolygonarea (point* p,intN) {DoubleArea =0.0;  for(inti =1; I < n1; i++) Area+ = Cross (p[i]-p[0],p[i+1]-p[0]); returnarea/2.0;} Point P[MAXN], CH[MAXN];BOOLCMP (Point A, point B) {if(dcmp (a.x-b.x) = =0)returnDCMP (A.Y-A.Y) <=0; returnDCMP (a.x-b.x) <0;}//output n points, output CH as the points contained in the convex package//If you do not want a point on the edge <= to < Enter No DuplicatesintConvexhull (point* p,intN, point*ch) {sort (p, p+ N);//Compare x First, compare y dictionary order    intm =0;  for(inti =0; I < n; i++) {         while(M >1&& Cross (ch[m-1]-ch[m-2], p[i]-ch[m-2]) <=0) m--; Ch[m++] =P[i]; }    intK =m;  for(inti = n-2; I >=0; i--) {         while(M > K && Cross (ch[m-1]-ch[m-2], p[i]-ch[m-2]) <=0) m--; Ch[m++] =P[i]; }    if(N >1) m--; returnm;}intMainintargcChar Const*argv[]) {    intT; scanf ("%d", &T);  while(t--) {        intN, cnt =0; scanf ("%d", &N); DoubleARA =0.0;  for(inti =0; i < N; i++) {            Doublex, Y, W, H, J; scanf ("%LF%LF%LF%LF%LF", &x, &y, &w, &h, &j); DoubleAng =-(j/180.0)*PI; Point O=Point (x, y); P[cnt+ +] = O + Rotate (Vector (w/2, h/2), ANG); P[cnt+ +] = O + Rotate (Vector (-w/2, h/2), ANG); P[cnt+ +] = O + Rotate (Vector (w/2,-h/2), ANG); P[cnt+ +] = O + Rotate (Vector (-w/2,-h/2), ANG); ARA+ = w*h; }        intm =convexhull (P, CNT, CH); DoubleA =polygonarea (CH, m); printf ("%.1LF%%\n", ara* -/A); }    return 0;}

uva–10652 Board wrapping[Convex bag]