Comprehensive example demonstrating Aleph-w's AHMapping class. More...

#include <iostream>
#include <iomanip>
#include <string>
#include <ah-mapping.H>
#include <tpl_dynArray.H>

Include dependency graph for mapping_example.C:

Functions
void	print_header (const string &title)

void	print_subheader (const string &subtitle)

void	demo_department_codes ()

void	demo_variadic_constructor ()

void	demo_numeric_mapping ()

void	demo_encoding_decoding ()

void	demo_modifiable_mapping ()

void	demo_city_coordinates ()

int	main ()

Detailed Description

Comprehensive example demonstrating Aleph-w's AHMapping class.

This example demonstrates AHMapping, a bidirectional key-value mapping container that provides efficient lookups in both directions. Unlike standard maps that only support forward lookup (key → value), AHMapping enables efficient reverse lookup (value → key) as well.

What is AHMapping?

AHMapping is a specialized container for bidirectional mappings:

Forward lookup: O(log n) - find value given key
Reverse lookup: O(log n) - find key given value (via inverse mapping)
Dual structure: Maintains both key→value and value→key mappings
Functional operations: Supports for_each and other functional ops

Key Features

Bidirectional Lookup

Forward: mapping[key] → returns value
Reverse: mapping.inverse()[value] → returns key
Both operations are O(log n) efficient

Data Structure

Uses balanced BST internally (typically Red-Black tree)
Maintains two mappings: forward and inverse
Automatic synchronization between mappings

Operations

Insert: Add key-value pair (updates both mappings)
Lookup: Find value by key or key by value
Iteration: Iterate over all pairs
Functional: Apply functions to all pairs

Use Cases

Translation Tables

Language codes ↔ names: "en" ↔ "English", "es" ↔ "Spanish"
Currency codes ↔ symbols: "USD" ↔ "$", "EUR" ↔ "€"
Country codes ↔ names: "CO" ↔ "Colombia", "US" ↔ "United States"

ID Mappings

User ID ↔ username: 12345 ↔ "john_doe"
Product ID ↔ name: 789 ↔ "Widget Pro"
Session ID ↔ user: "abc123" ↔ user_object

Configuration Parameters

Setting name ↔ value: "theme" ↔ "dark", "language" ↔ "es"
Environment variables: "PATH" ↔ "/usr/bin:/usr/local/bin"
Feature flags: "new_ui" ↔ true, "beta_features" ↔ false

Encoding/Decoding Schemes

Character encoding: ASCII codes ↔ characters
Base conversion: Decimal ↔ hexadecimal
Protocol mapping: Internal codes ↔ external codes

Colombian Theme

Examples use Colombian data for cultural relevance:

Departments: "ANT" ↔ "Antioquia", "CUN" ↔ "Cundinamarca"
Cities: "BOG" ↔ "Bogotá", "MED" ↔ "Medellín"
Cultural elements: Colombian regions, landmarks, traditions

Comparison with Standard Maps

Feature	std::map	AHMapping
Forward lookup	O(log n)	O(log n)
Reverse lookup	O(n)	O(log n)
Memory	O(n)	O(n)
Bidirectional	No	Yes

Advantage: AHMapping provides efficient reverse lookup without maintaining a separate reverse map manually.

Complexity

Operation	Complexity	Notes
Insert	O(log n)	Updates both mappings
Forward lookup	O(log n)	Key → value
Reverse lookup	O(log n)	Value → key
Iteration	O(n)	All pairs
Size	O(1)	Number of pairs

Usage Example

AHMapping<string, string> translations;
 
// Add translations
translations.insert("en", "English");
translations.insert("es", "Spanish");
translations.insert("fr", "French");
 
// Forward lookup
string lang = translations["en"]; // "English"
 
// Reverse lookup
string code = translations.inverse()["Spanish"]; // "es"