A graph Airline Routes A GraphG is represented as a pair <V, E>, where V is a set of vertices <Bos, SFO, LA, Dallas, Wash DO E is a set of (directed)edges &<SFO, Bos>. ≤SFO,LA> An edge is a pair <vl, v2> of vertices, where <LA, Dallas> 2 is the head of the edge, <Dallas. Wash DC> .and vl is the tail of the edge Snas witha, Spring 03 > a Solution is a state sequence Problem Solving searches Paths R ched paths using a tree Bran withams, Spring 038 Brian Williams, Spring 03 16 A Graph San Fran Boston LA Dallas Wash DC Airline Routes A Graph G is represented as a pair <V,E>, where: • V is a set of vertices • E is a set of (directed) edges An edge is a pair <v1, v2> of vertices, where • v2 is the head of the edge, •and v1 is the tail of the edge < {Bos, SFO, LA, Dallas, Wash DC} {<SFO, Bos>, <SFO, LA> <LA, Dallas> <Dallas, Wash DC> . . .} > Brian Williams, Spring 03 17 A Solution is a State Sequence: Problem Solving Searches Paths C S B G A D S D A C Represent searched paths using a tree. <S, A, D, C>