msjidandClaude Haiku 4.5
5d2fddb4c1
Update README with detailed explanation of interval_map implementation, including overview, key characteristics, usage examples, build instructions, and real-world use cases. Co-Authored-By: Claude Haiku 4.5 <[email protected]> Claude-Session: https://claude.ai/code/session_01Te4uaebdDpT3hbdtrkcofD
75 lines
2.5 KiB
Plaintext
75 lines
2.5 KiB
Plaintext
# Interval Map Implementation
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A template-based C++ implementation of an efficient interval map data structure that maps intervals (ranges) of keys to values, rather than individual key-value pairs.
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## Overview
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`interval_map<K, V>` is a specialized container that associates values with continuous intervals of keys. Instead of storing a value for every single key, it compresses storage by representing contiguous ranges that map to the same value.
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### Key Characteristics
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- **Efficient Storage**: Stores only the boundaries where values change, reducing memory overhead compared to individual key mappings
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- **Standard Library Integration**: Built on top of `std::map` for reliable performance and familiarity
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- **Template-Based**: Supports any comparable key type (`K`) and any value type (`V`)
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- **Interval Semantics**: Follows C++ conventions with half-open intervals `[keyBegin, keyEnd)`
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## How It Works
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### Constructor
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```cpp
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interval_map(V const& val, K k_range=1000)
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```
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Initializes the map with a default value that covers the entire key range. Pre-populates the internal map with entries for optimization purposes.
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### assign() Method
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```cpp
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void assign(K const& keyBegin, K const& keyEnd, V const& val)
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```
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Assigns a value `val` to the interval `[keyBegin, keyEnd)`.
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- If `keyBegin >= keyEnd`, the interval is empty and nothing is done
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- Overwrites any previous values in this interval
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- Uses `std::map::lower_bound()` for efficient O(log n) interval lookup
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### Operator[]
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```cpp
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V const& operator[](K const& key) const
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```
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Performs efficient O(log n) lookup to retrieve the value associated with a given key.
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## Usage Example
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```cpp
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interval_map<int, char> m('A', 100); // Initialize with 'A' covering [0, 100)
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m.assign(-10, 50, 'B'); // Assign 'B' to [-10, 50)
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m['25']; // Returns 'B'
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m['75']; // Returns 'A'
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```
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## Building and Running
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### Compile
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```bash
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g++ -std=c++11 -o interval_map main.cpp
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```
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### Run
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```bash
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./interval_map
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```
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## Implementation Details
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This implementation demonstrates:
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- Mastery of `std::map` operations (`lower_bound`, `upper_bound`, `insert`)
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- Efficient interval range manipulation
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- Template metaprogramming with multiple template parameters
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- Memory-efficient data structure design
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- Proper use of C++ Standard Library conventions
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## Use Cases
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- Graphics rendering (color transitions)
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- Time-based event scheduling
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- Segment compression and querying
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- Network routing tables
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- Configuration management with ranges |