Question

we consider a graph G= (V, E), with n=|V| and m=|E|. Describe an O(n+m) time algorithm...

we consider a graph G= (V, E), with n=|V| and m=|E|.

Describe an O(n+m) time algorithm to find such a vertex w. Hint: a depth-first search from u might be helpful.

Homework Answers

Answer #1

A graph G=(V,E), with n=|v| and m=|E|

If the time complexity is O(n+m) then this is depth- first-search because in depth-first-search (DFS)

Recursively explore graph, backtracking as necessary. In DFS stack data structure is used.

  • Visit each vertex once in DFS alone that's why its O(v)
  • DFS (V1, V2...., Vn) called at most once per vertex . That's why we have to pay | adj[V] |

therefore, O( summation of |adj [V]|)= O(E)

That's why we can say the time complexity  of DFS is O(V+E) or O(m+n)

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
You are given a directed acyclic graph G(V,E), where each vertex v that has in-degree 0...
You are given a directed acyclic graph G(V,E), where each vertex v that has in-degree 0 has a value value(v) associated with it. For every other vertex u in V, define Pred(u) to be the set of vertices that have incoming edges to u. We now define value(u) = ?v∈P red(u) value(v). Design an O(n + m) time algorithm to compute value(u) for all vertices u where n denotes the number of vertices and m denotes the number of edges...
Consider a minimum spanning tree for a weighted graph G= (V, E)and a new edge e,...
Consider a minimum spanning tree for a weighted graph G= (V, E)and a new edge e, connecting two existing nodes in V. Explain how to find a minimum spanning tree of the new graph in O(n)time, where n is the number of nodes in the graph. Prove correctness of the algorithm and justify the running time
Problem 2. Consider a graph G = (V,E) where |V|=n. 2(a) What is the total number...
Problem 2. Consider a graph G = (V,E) where |V|=n. 2(a) What is the total number of possible paths of length k ≥ 0 in G from a given starting vertex s and ending vertex t? Hint: a path of length k is a sequence of k + 1 vertices without duplicates. 2(b) What is the total number of possible paths of any length in G from a given starting vertex s and ending vertex t? 2(c) What is the...
Let G be a graph or order n with independence number α(G) = 2. (a) Prove...
Let G be a graph or order n with independence number α(G) = 2. (a) Prove that if G is disconnected, then G contains K⌈ n/2 ⌉ as a subgraph. (b) Prove that if G is connected, then G contains a path (u, v, w) such that uw /∈ E(G) and every vertex in G − {u, v, w} is adjacent to either u or w (or both).
Suppose that we generate a random graph G = (V, E) on the vertex set V...
Suppose that we generate a random graph G = (V, E) on the vertex set V = {1, 2, . . . , n} in the following way. For each pair of vertices i, j ∈ V with i < j, we flip a fair coin, and we include the edge i−j in E if and only if the coin comes up heads. How many edges should we expect G to contain? How many cycles of length 3 should we...
Let G = (V,E) be a graph with n vertices and e edges. Show that the...
Let G = (V,E) be a graph with n vertices and e edges. Show that the following statements are equivalent: 1. G is a tree 2. G is connected and n = e + 1 3. G has no cycles and n = e + 1 4. If u and v are vertices in G, then there exists a unique path connecting u and v.
Let us consider Boruvka/Sollin's algorithm as shown . Note that Boruvka/Sollin algorithm selects several edges for...
Let us consider Boruvka/Sollin's algorithm as shown . Note that Boruvka/Sollin algorithm selects several edges for inclusion in T at each stage. It terminates when only one tree at the end of a stage or no edges to be selected. One Step of Boruvka/Sollin's Algorithm 1: Find minimum cost edge incident to every vertex. 2: Add to tree T. 3: Remove cycle if any. 4: Compress and clean graph (eliminate multiple edges). (a) Suppose that we run k phases of...
Labor Relations- Chapter 5- G o v e r n m e n t s ,...
Labor Relations- Chapter 5- G o v e r n m e n t s , L a b o u r R e l a t i o n s B o a r d s , a n d O t h e r P a r t i e s Case Study- Quality Inn & Suites Brantford v. UFCW Local 175 In January 2012 the Ontario Labour Relations Board was asked to consider an application for the...
1. Given an n-element array A, Algorithm X executes an O(n)-time computation for each even number...
1. Given an n-element array A, Algorithm X executes an O(n)-time computation for each even number in A and an O(log n)-time computation for each odd number in A. What is the best-case running time of Algorithm X? What is the worst-case running time of Algorithm X? 2. Given an array, A, of n integers, give an O(n)-time algorithm that finds the longest subarray of A such that all the numbers in that subarray are in sorted order. Your algorithm...
Consider an undirected graph G = (V, E) with an injective cost function c: E →...
Consider an undirected graph G = (V, E) with an injective cost function c: E → N. Suppose T is a minimum spanning tree of G for cost function c. If we replace each edge cost c(e), e ∈ E, with cost c'(e) = c(e)2 for G, is T still a minimum spanning tree of G? Briefly justify your answer.
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT