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I often see my tutor referencing to both adjacency lists and adjacency matrix in Graph theory
But I still don't understand the difference?
Any help please?

Ahmed Nabil
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    [This article](https://www.geeksforgeeks.org/graph-and-its-representations/) might help you. – Pyromonk Dec 26 '17 at 04:28
  • Related post - [What is better, adjacency lists or adjacency matrices for graph problems in C++?](https://stackoverflow.com/q/2218322/465053) – RBT Jul 03 '18 at 23:42

1 Answers1

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Adjacency list shows which nodes are connected to which, in the following format:

2 3 4 5
1 4
1 5 4
1 2 5 3
1 3 4

This means node 1 is connected to nodes 2, 3, 4 and 5, node 2 is connected to 1 and 4, and so on.

The adjacency matrix, on the other hand, does it in the following matrix format:

01111
10010
10011
11101
10110

It shows that if the 1st node and 2nd node are connected, there is a 1 at the grid[1][2] position, and 0 if the 2 nodes aren't connected, or if they are the same nodes. Hope this helps!

Asesh
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QuIcKmAtHs
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