什么是最短通路问题： In a shortest-paths problem,we are given a weighted,directed graph G=(V,E),with weight function w:ER mapping edges to real-valued weights.The weight w(p)of path p=(vo.v1...v)is the sum of the weights of its constituent edges: 问题1： k w(p）=w(-1,). 输入是什么？输出是 i=1 什么？ We define the shortest-path weight 8(u,v)from u to v by min()ithere isa pathfrom o otherwise A shortest path from vertex u to vertex v is then defined as any path p with weight w(p)=8u,)什么是最短通路问题?