2011-10-10 11:27:24 +04:00
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(function(){function c(a){var b=0,c=0;for(;;){if(a(b,c))return[b,c];b===0?(b=c+1,c=0):(b-=1,c+=1)}}function d(a,b,c,d){var e,f,g,h,i,j,k;return e=d[a],f=e[0],g=e[1],e=d[b],h=e[0],i=e[1],e=d[c],j=e[0],k=e[1],(k-g)*(h-f)-(i-g)*(j-f)>0}function e(a,b,c){return(c[0]-b[0])*(a[1]-b[1])<(c[1]-b[1])*(a[0]-b[0])}function f(a,b,c,d){var e=a[0],f=b[0],g=c[0],h=d[0],i=a[1],j=b[1],k=c[1],l=d[1],m=e-g,n=f-e,o=h-g,p=i-k,q=j-i,r=l-k,s=(o*p-r*m)/(r*n-o*q);return[e+s*n,i+s*q]}function h(a,b){var c={list:a.map(function(a,b){return{index:b,x:a[0],y:a[1]}}).sort(function(a,b){return a.y<b.y?-1:a.y>b.y?1:a.x<b.x?-1:a.x>b.x?1:0}),bottomSite:null},d={list:[],leftEnd:null,rightEnd:null,init:function(){d.leftEnd=d.createHalfEdge(null,"l"),d.rightEnd=d.createHalfEdge(null,"l"),d.leftEnd.r=d.rightEnd,d.rightEnd.l=d.leftEnd,d.list.unshift(d.leftEnd,d.rightEnd)},createHalfEdge:function(a,b){return{edge:a,side:b,vertex:null,l:null,r:null}},insert:function(a,b){b.l=a,b.r=a.r,a.r.l=b,a.r=b},leftBound:function(a){var b=d.leftEnd;do b=b.r;while(b!=d.rightEnd&&e.rightOf(b,a));return b=b.l,b},del:function(a){a.l.r=a.r,a.r.l=a.l,a.edge=null},right:function(a){return a.r},left:function(a){return a.l},leftRegion:function(a){return a.edge==null?c.bottomSite:a.edge.region[a.side]},rightRegion:function(a){return a.edge==null?c.bottomSite:a.edge.region[g[a.side]]}},e={bisect:function(a,b){var c={region:{l:a,r:b},ep:{l:null,r:null}},d=b.x-a.x,e=b.y-a.y,f=d>0?d:-d,g=e>0?e:-e;return c.c=a.x*d+a.y*e+(d*d+e*e)*.5,f>g?(c.a=1,c.b=e/d,c.c/=d):(c.b=1,c.a=d/e,c.c/=e),c},intersect:function(a,b){var c=a.edge,d=b.edge;if(!c||!d||c.region.r==d.region.r)return null;var e=c.a*d.b-c.b*d.a;if(Math.abs(e)<1e-10)return null;var f=(c.c*d.b-d.c*c.b)/e,g=(d.c*c.a-c.c*d.a)/e,h=c.region.r,i=d.region.r,j,k;h.y<i.y||h.y==i.y&&h.x<i.x?(j=a,k=c):(j=b,k=d);var l=f>=k.region.r.x;return l&&j.side==="l"||!l&&j.side==="r"?null:{x:f,y:g}},rightOf:function(a,b){var c=a.edge,d=c.region.r,e=b.x>d.x;if(e&&a.side==="l")return 1;if(!e&&a.side==="r")return 0;if(c.a===1){var f=b.y-d.y,g=b.x-d.x,h=0,i=0;!e&&c.b<0||e&&c.b>=0?i=h=f>=c.b*g:(i=b.x+b.y*c.b>c.c,c.b<0&&(i=!i),i||(h=1));if(!h){var j=d.x-c.region.l.x;i=c.b*(g*g-f*f)<j*f*(1+2*g/j+c.b*c.b),c.b<0&&(i=!i)}}else{var k=c.c-c.a*b.x,l=b.y-k,m=b.x-d.x,n=k-d.y;i=l*l>m*m+n*n}return a.side==="l"?i:!i},endPoint:function(a,c,d){a.ep[c]=d;if(!a.ep[g[c]])return;b(a)},distance:function(a,b){var c=a.x-b.x,d=a.y-b.y;return Math.sqrt(c*c+d*d)}},f={list:[],insert:function(a,b,c){a.vertex=b,a.ystar=b.y+c;for(var d=0,e=f.list,g=e.length;d<g;d++){var h=e[d];if(a.ystar>h.ystar||a.ystar==h.ystar&&b.x>h.vertex.x)continue;break}e.splice(d,0,a)},del:function(a){for(var b=0,c=f.list,d=c.length;b<d&&c[b]!=a;++b);c.splice(b,1)},empty:function(){return f.list.length===0},nextEvent:function(a){for(var b=0,c=f.list,d=c.length;b<d;++b)if(c[b]==a)return c[b+1];return null},min:function(){var a=f.list[0];return{x:a.vertex.x,y:a.ystar}},extractMin:function(){return f.list.shift()}};d.init(),c.bottomSite=c.list.shift();var h=c.list.shift(),i,j,k,l,m,n,o,p,q,r,s,t,u;for(;;){f.empty()||(i=f.min());if(h&&(f.empty()||h.y<i.y||h.y==i.y&&h.x<i.x))j=d.leftBound(h),k=d.right(j),o=d.rightRegion(j),t=e.bisect(o,h),n=d.createHalfEdge(t,"l"),d.insert(j,n),r=e.intersect(j,n),r&&(f.del(j),f.insert(j,r,e.distance(r,h))),j=n,n=d.createHalfEdge(t,"r"),d.insert(j,n),r=e.intersect(n,k),r&&f.insert(n,r,e.distance(r,h)),h=c.list.shift();else if(!f.empty())j=f.extractMin(),l=d.left(j),k=d.right(j),m=d.right(k),o=d.leftRegion(j),p=d.rightRegion(k),s=j.vertex,e.endPoint(j.edge,j.side,s),e.endPoint(k.edge,k.side,s),d.del(j),f.del(k),d.del(k),u="l",o.y>p.y&&(q=o,o=p,p=q,u="r"),t=e.bisect(o,p),n=d.createHalfEdge(t,u),d.insert(l,n),e.endPoint(t,g[u],s),r=e.intersect(l,n),r&&(f.del(l),f.insert(l,r,e.distance(r,o))),r=e.intersect(n,m),r&&f.insert(n,r,e.distance(r,o));else break}for(j=d.right(d.leftEnd);j!=d.rightEnd;j=d.right(j))b(j.edge)}function i(){return{leaf:!0,nodes:[],point:null}}function j(a,b,c,d,e,f){if(!a(b,c,d,e,f)){var g=(c+e)*.5,h=(d+f)*.5,i=b.nodes;i[0]&&j(a,i[0],c,d,g,h),i[1]&&j(a,i[1],g,d,e,h),i[2]&&
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