1
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‫So now we're going to create our remove edge function.

2
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‫And as the name would imply, it's just going to remove the connection between two vertices.

3
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‫In the adjacency list it will look like this.

4
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‫So I'm going to move this down and bring that edge back because we haven't removed it yet and start

5
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‫our code like this and we'll pass it to vertices vertex one and vertex two.

6
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‫And we'll say adjacency list at Vertex one.

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‫And when we do this, it's going to return the value and the key value pair and the value is going to

8
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‫be this unordered set.

9
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‫And when we return that we can use the member functions on unordered sets and we can say erase vertex

10
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‫two and it removes Vertex two from that unordered set.

11
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‫And then we can do it the other way and remove vertex one like this.

12
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‫And of course, we can only do this if both of the vertices exist.

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‫And we'll check to make sure that they both do exist with this if statement.

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‫And if they do exist, we'll run those two lines of code and then we'll return.

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‫True.

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‫If one or both of them do not exist, will return false.

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‫So that is our entire remove edge function.

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‫We'll look at this code in a moment in vs code and when we do we'll create this graph and then we'll

19
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‫do a remove edge between A and B and then our graph will look like this.

20
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‫So now let's flip over to vs code and take a look at this.

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‫So there is our Remove Edge member function that we just created added to our graph class and I'll scroll

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‫up.

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‫And in our main function this creates our graph.

24
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‫These three lines create those three vertices A, B and C, and these three lines create the edges between

25
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‫all of them.

26
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‫And then with this line will print that out and I'll run this.

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‫And you can see we have our three vertices and each of the vertices have edges with the other two vertices.

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‫So I'm going to come over here and I'm going to add this line which will remove the edge between A and

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‫B, and now I'll run this.

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‫And you can see that the edge between A and B has been removed.

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‫And that is our function for Remove Edge.