Add Floyd–Warshall All-Pairs Shortest Path Algorithm Implementation in R

[iampratik13]

This PR introduces a complete and well-documented implementation of the Floyd–Warshall algorithm in R using an R6 class structure.

Overview

The FloydWarshall class computes shortest paths between all pairs of vertices in a weighted directed graph.
It supports positive and negative edge weights, detects negative cycles, and allows full path reconstruction.

Features

• All-pairs shortest path computation
• Handles negative edge weights (but not negative cycles)
• Detects negative cycles
• Supports disconnected components
• Provides distance and predecessor matrices
• Reconstructs shortest paths between any two vertices
• Includes multiple demonstration examples:
  • Simple weighted graph
  • Negative edge weights
  • Negative cycle detection
  • Disconnected components

Complexity

• Time Complexity: O(V³)
• Space Complexity: O(V²)

Demonstration

Run demonstrate_floyd_warshall() to execute sample graphs and visualize results.

This implementation enhances the R graph algorithms module with a core dynamic programming algorithm widely used in routing, optimization, and network analysis.

[Copilot]

Pull Request Overview

Adds a new R6-based implementation of the Floyd–Warshall all-pairs shortest paths algorithm, including utilities for path reconstruction, negative-cycle detection, and demonstration examples.

• Implements core O(V^3) Floyd–Warshall with distance and predecessor matrices
• Provides path reconstruction and negative cycle detection APIs
• Includes a demonstration function with multiple example graphs

[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 4 comments.