[lemma=□] □
[lemma=edge] □
[lemma=")"] □
For example , the Sn-packing problem ( where Sn is the set of stars of G having at most n edges ) is a simple generalization of the matching problem that turns out to be polynomial . The concept of " spring embedder " or " force-directed " layout algorithms , is to model a graph as a set of rings ( nodes ) connected by springs ( edges ) . What if then you threw out all the fringe software ( software near the edges ) and distilled the lot into an elegant library of commonly used stuff . Mathematician Leonard Euler ( 1707-1783 ) discovered a special relationship between the number of faces , edges and vertices of a polyhedron ( a polyhedron is a 3-dimensional object whose faces are polygons and a polygon is a closed 2-dimensional figure bound by straight edges ) . In this Chandra true-color X-Ray image the bright white sources ( and the blue source on the right most edge ) are cataclysmic variables , while the bright yellow source to lower center is a thermally emitting neutron star , in a quiescent low-mass x-ray binary . If and when you need the Taskbar , hold your mouse pointer over the side of the screen where it 's hiding ( you 'll be able to see its edge ) , and the Taskbar rises to the occasion . In this work , we developed a general and flexible formalism to describe visibility events based on sets of generators ( i.e ., vertices and edges ) . Judging distances ( example : bumping into things , placing objects too close to an edge ) Fluidity of movement ( example : getting out of the way of a moving ball , knocking things over ) Differentiating colors or similarly shaped letters and numbers ( example : b , d ; p , q ; 6,9 ; 2,5 ) . Wise agents , top producers at the top of their earning curve , stay on the cutting edge of technology ( not the bleeding edge ) .