( (ba ( (da ( ( figure example of depth-first search traversal on an undirected graph starting at vertex we assume that vertex' adjacencies are considered in alphabetical order visited vertices and explored edges are highlightedwith discovery edges drawn as solid lines and nontree (backedges as dashed lines(ainput graph(bpath of tree edgestraced from until back edge ( ,cis examined(creaching fwhich is dead end(dafter backtracking to iresuming with edge ( , )and hitting another dead end at (eafter backtracking to gcontinuing with edge ( , )and hitting another dead end at ( final result