"Hdoj" 3285 convex Hull of Lattice Points

Convex hull template title.

1 /*3285*/2#include <iostream>3#include <cstdio>4#include <cstring>5#include <cmath>6#include <algorithm>7 using namespacestd;8 9 #defineMAXN 55Ten  Onetypedefstruct { A     intx, y; - } point_t; -  the point_t POINTS[MAXN]; - point_t STACK[MAXN]; - inttop; -  + voidOutputint); -  + DoubleDist (point_t A, point_t b) { A     returnsqrt1.0* (a.x-b.x) * (a.x-b.x) + (A.Y-B.Y) * (a.y-b.y)); at } -  - intDist2 (point_t A, point_t b) { -     return(a.x-b.x) * (a.x-b.x) + (A.Y-B.Y) * (a.y-b.y); - } -  in intCross (point_t A, point_t B, point_t c) { -     return(b.x-a.x) * (C.Y-A.Y)-(c.x-a.x) * (b.y-a.y); to } +  - BOOLComp (point_t A, point_t b) { the     intm = Cross (points[0], A, b); *     returnM>0|| (m==0&& Dist2 (points[0], a) <dist2 (points[0], b)); $ }Panax Notoginseng  - voidGraham (intN) { the point_t p; +     intI, J, K; A      thep = points[0]; +K =0; -      for(i=1; i<n; ++i) { $         if(points[i].x<p.x | | (points[i].x==p.x && points[i].y<p.y)) { $p =Points[i]; -K =i; -         } the     } -Points[k] = points[0];Wuyipoints[0] =p; the      -Sort (points+1, points+N, comp); Wu      -stack[0] = points[0]; Aboutstack[1] = points[1]; $top =1; -      -      for(i=2; i<n; ++i) { -          while(Top && Cross (stack[top-1], Stack[top], points[i]) <=0) A--top; +Stack[++top] =Points[i]; the     } - } $  the intMain () { the     intT, Case_n; the     intN; the     intI, J, K; - point_t p; in      the #ifndef Online_judge theFreopen ("data.in","R", stdin); About #endif the  thescanf"%d", &t); the      while(t--) { +scanf"%d%d", &case_n, &n); -          for(i=0; i<n; ++i) thescanf"%d%d", &points[i].x, &points[i].y);Bayi Graham (n); theprintf"%d%d\n", Case_n, top+1); thep = stack[0]; -K =0; -          for(i=1; i<=top; ++i) { the             if(Stack[i].y>p.y | | (Stack[i].y==p.y && stack[i].x<p.x)) { thep =Stack[i]; theK =i; the             } -         } the          for(I=k; i>=0; --i) theprintf"%d%d\n", stack[i].x, stack[i].y); the          for(I=top; i>k;--i)94printf"%d%d\n", stack[i].x, stack[i].y); the     } the  the     return 0;98}

"Hdoj" 3285 convex Hull of Lattice Points