word-ladder-gen

Generate and solve word ladder puzzles.

Install

npm install word-ladder-gen

Usage

import { generate, solve, validate_word } from 'word-ladder-gen';

generate() - Generate a random puzzle:

generate({ length: 4, minSteps: 3, maxSteps: 5 })

{
  "word1": "cold",
  "word2": "warm",
  "word1freqrank": 412,
  "word2freqrank": 309,
  "minSteps": 4,
  "optimalSolution": ["cold", "cord", "card", "ward", "warm"]
}

solve() - Solve a specific puzzle:

solve('head', 'tail')

{
  "word1": "head",
  "word2": "tail",
  "word1freqrank": 87,
  "word2freqrank": 497,
  "minSteps": 5,
  "optimalSolution": ["head", "heal", "teal", "tell", "tall", "tail"]
}

validate_word() - Check if word exists:

validate_word('test')      // true
validate_word('test', 4)   // true (checks 4-letter dictionary only)
validate_word('xyzq')      // false

API

generate(options)

| Option | Default | Description | |--------|---------|-------------| | length | 4 | Word length (4, 5, or 6) | | minSteps | 2 | Minimum solution steps | | maxSteps | 10 | Maximum solution steps | | frequency | 2000 | Use top N most common words |

Dictionary sizes: 3,903 (4-letter), 8,636 (5-letter), 15,232 (6-letter).

Returns puzzle object or null if no valid puzzle found.

solve(word1, word2)

Returns shortest path between two words, or null if unsolvable.

validate_word(word, length?)

Returns true if word exists in dictionary.

Graph Data

Pre-computed adjacency graphs are exported for direct access:

import { graph4, graph5, graph6 } from 'word-ladder-gen';

graph4['cold']  // → ['bold', 'fold', 'gold', 'hold', 'mold', 'sold', 'told', 'cod', 'cola', 'cole', 'colt', 'cols']

Each graph maps words to arrays of valid one-letter transformations.

License

MIT