1. Can you get there from here?
Graphs and Searches
Can you get there from here?

2. Graph
A graph G is a set of vertices V = {v1, v2,…, vn} and a set E of pairs of vertices known as edges E = {(vi, vj): 1 ≤ i, j ≤ n}
Graphs may be represented pictorially 3 1 2 7 4 6 5 9 8
12/6/2018
DRAFT

3. Graph Graphs may be represented computationally Adjacency lists
Adjacency matrices V
Is adjacent to 1
4, 5 2 6 3
6, 7 4
1, 8 5
2, 3, 8, 9 7
3, 9 8
4, 5, 6, 9 9
6, 7, 8 3 1 2 7 4 6 5 9 8
12/6/2018
DRAFT

4. Breadth First Search Bfs(v) visited[v] = 1 u = v
Create an empty queue Q
Loop
For all vertices w that are adjacent to u
If visited[w] = 0
Add w to Q
Mark w as visited, visited[w]=1
If Q is empty, return
Remove head of Q and place in u
Repeat
12/6/2018
DRAFT

5. Depth First Search Dfs(v) Example Bfs and Dfs code link visited[v] = 1
For each vertex w adjacent to v
If visited[w] == 0, then Dfs(w)
Example Bfs and Dfs code link
12/6/2018
DRAFT