Explore Graph Path Existence in Python

Introduction

In computer science, a graph is a collection of nodes that are connected to each other through edges. Graphs are widely used to model real-world scenarios such as social networks, transportation systems, and computer networks. One of the fundamental problems in graph theory is to determine whether there is a path between two nodes in a graph. In this challenge, we will write a Python function to solve this problem.

Skills Graph

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Graph Path Exists

Problem

Given a directed graph and two nodes, write a Python function to determine whether there is a path between the two nodes.

Requirements

To solve this problem, we need to make the following assumptions:

The graph is directed.
We already have Graph and Node classes.
The graph is connected.
The inputs are valid.
The solution fits memory.

Example Usage

Suppose we have the following graph:

graph.add_edge(0, 1, 5)
graph.add_edge(0, 4, 3)
graph.add_edge(0, 5, 2)
graph.add_edge(1, 3, 5)
graph.add_edge(1, 4, 4)
graph.add_edge(2, 1, 6)
graph.add_edge(3, 2, 7)
graph.add_edge(3, 4, 8)

We can use the following function to determine whether there is a path between two nodes:

search_path(start=0, end=2) -> True
search_path(start=0, end=0) -> True
search_path(start=4, end=5) -> False

The first two function calls return True because there is a path between the start and end nodes. The last function call returns False because there is no path between the start and end nodes.

Summary

In this challenge, we wrote a Python function to determine whether there is a path between two nodes in a directed graph. We made several assumptions about the graph and the inputs to simplify the problem. The function can be used to solve a wide range of real-world problems that involve graph traversal.

Graph Path Exists

Introduction

Skills Graph

Graph Path Exists

Problem

Requirements

Example Usage

Summary

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