Implement restaurant delivery zones with Union-Find

[shubhambhar007]

This implementation tracks restaurant openings in a city grid and manages delivery zones using the Union-Find data structure for efficient connected component tracking.

Add Restaurant Delivery Zones Implementation with Union-Find
Summary
Implements an efficient city grid system for tracking restaurant openings and managing delivery zones using the Union-Find (Disjoint Set Union) data structure.

Features

• Restaurant Management: Track multiple restaurants per city block with efficient opening operations
• Delivery Zone Tracking: Automatically manage connected delivery zones using Union-Find algorithm
• Path Compression: Optimized find operation with path compression for near-constant time complexity
• Union by Rank: Efficient set merging to maintain balanced tree structure
• Key Functionality
• open_restaurant(r, c): Add restaurant at grid position with automatic zone merging
• count_open_restaurants(): Get total count of opened restaurants
• block_has_open_restaurants(r, c): Check if specific block has restaurants
• count_delivery_zones(): Get number of connected delivery zones

Time Complexity

• Initialize: O(rows × cols)
• Open Restaurant: O(α(n)) amortized, where α is inverse Ackermann function (practically constant)
• Query Operations: O(1) for counts and block checks
• Space Complexity
• O(rows × cols) for grid state and union-find structure

Demo & Testing
Includes comprehensive example usage demonstrating:

• Restaurant opening and zone formation
• Adjacent block merging
• Multiple restaurants per block handling
• Grid visualization
• Real-time zone count tracking
• Implementation Details
• Uses iterative path compression for find operations
• Implements union by rank for balanced merging
• Maintains separate counters for total restaurants vs active blocks
• Supports 4-directional connectivity (up, down, left, right)