标签:blog os io for art div ar line
内部也是相交
#include <iostream> #include <cstdio> #include <cstring> #include <algorithm> using namespace std; struct point{ int x,y; }; struct edge{ point start,end; }line[4],the; void swaped(int &x,int &y){ int tmp=x; x=y; y=tmp; } int multi(point p1,point p2, point p0){ return (p1.x-p0.x)*(p2.y-p0.y)-(p2.x-p0.x)*(p1.y-p0.y); } bool cross(edge v1, edge v2){ if(max(v1.start.x,v1.end.x)>=min(v2.start.x,v2.end.x)&& max(v2.start.x,v2.end.x)>=min(v1.start.x,v1.end.x)&& max(v1.start.y,v1.end.y)>=min(v2.start.y,v2.end.y)&& max(v2.start.y,v2.end.y)>=min(v1.start.y,v1.end.y)&& multi(v2.start,v1.end,v1.start)*multi(v1.end,v2.end,v1.start)>=0&& multi(v1.start,v2.end,v2.start)*multi(v2.end,v1.end,v2.start)>=0) return true; return false; } /* bool cross(point &a, point &b, point &c, point &d) { if (min(a.x, b.x) > max(c.x, d.x) || min(a.y, b.y) > max(c.y, d.y) || min( c.x, d.x) > max(a.x, b.x) || min(c.y, d.y) > max(a.y, b.y)) return 0; double h, i, j, k; h = (b.x - a.x) * (c.y - a.y) - (b.y - a.y) * (c.x - a.x); i = (b.x - a.x) * (d.y - a.y) - (b.y - a.y) * (d.x - a.x); j = (d.x - c.x) * (a.y - c.y) - (d.y - c.y) * (a.x - c.x); k = (d.x - c.x) * (b.y - c.y) - (d.y - c.y) * (b.x - c.x); return h * i <= 0 && j * k <= 0; }*/ int main(){ int T; int xleft,ytop,xright,ybottom; int xstart,ystart,xend,yend; scanf("%d",&T); while(T--){ scanf("%d%d%d%d%d%d%d%d",&xstart,&ystart,&xend,¥d,&xleft,&ytop,&xright,&ybottom); the.start.x=xstart; the.start.y=ystart; the.end.x=xend; the.end.y=yend; if(xleft>xright) swaped(xleft,xright); if(ytop<ybottom) swaped(ytop,ybottom); line[0].start.x=xleft; line[0].start.y=ytop; line[0].end.x=xright; line[0].end.y=ytop; line[1].start.x=xleft; line[1].start.y=ybottom; line[1].end.x=xright; line[1].end.y=ybottom; line[2].start.x=xleft; line[2].start.y=ybottom; line[2].end.x=xleft; line[2].end.y=ytop; line[3].start.x=xright; line[3].start.y=ybottom; line[3].end.x=xright; line[3].end.y=ytop; bool flag=true; for(int i=0;i<4;i++){ if(cross(the,line[i])){ flag=false; break; } } if(flag){ if(xstart>=min(xleft,xright)&&xstart<=max(xleft,xright)&& ystart>=min(ytop,ybottom)&&ystart<=max(ytop,ybottom)){ flag=false; } else if(xend>=min(xleft,xright)&&xend<=max(xleft,xright)&& yend>=min(ytop,ybottom)&¥d<=max(ytop,ybottom)) flag=false; } if(flag){ printf("F\n"); } else printf("T\n"); } return 0; }
标签:blog os io for art div ar line
原文地址:http://www.cnblogs.com/jie-dcai/p/3869778.html