How can I represent graphs in code?

How can I represent graphs in code?

You can represent graphs in code using various data structures like adjacency lists, adjacency matrices, or edge lists. Which one are you interested in?

What's the difference between an adjacency list and an adjacency matrix?

An adjacency list uses a list of lists to represent connections, which is more space-efficient for sparse graphs. An adjacency matrix uses a 2D array, which is easier for dense graphs but consumes more memory.

Can you show me an example of an adjacency list in Python?

Sure! Here's a simple example:

class Graph:
    def __init__(self):
        self.graph = {}

    def add_edge(self, u, v):
        if u not in self.graph:
            self.graph[u] = []
        self.graph[u].append(v)

What about representing weighted graphs?

For weighted graphs, you can modify the adjacency list to store tuples of (neighbor, weight). Would you like to see an example?