Description
Build one-letter adjacency from a supplied lexicon, draw reachable endpoints, and return a delegated shortest ladder while allowing alternate solutions.
A generated practice exercise contains a prompt and an answer key under a specific rule set. A planted answer establishes one possible solution; only an explicit enumeration or uniqueness check establishes whether alternatives exist.
Build one-letter adjacency from a supplied lexicon, draw reachable endpoints, and return a delegated shortest ladder while allowing alternate solutions.
When to use this tool
Use this generator to create reproducible word ladder challenge cases from the supplied model or bank. Inspect the returned evidence before using cases in a test or exercise.
How to use the tool and how it works
- Supply words, minimumSteps, provenance in the field shapes below. Set seed when you need an explicit replay.
- Run the tool and correct any input error. For generated controls, distinguish a successful fixture containing an invalid case from failure to generate the fixture.
- Read puzzle, answer, edges, eligiblePairCount, provenance. Use the conventions below and keep answer-bearing fields separate when presenting an exercise.
Build an undirected adjacency graph between equal-length supplied words at Levenshtein distance one. Find endpoint pairs whose shortest distance meets minimumSteps, draw a pair and delegate the shortest answer ladder while retaining the graph and eligible-pair count.1
Delegated operations used for this result: levenshtein; shortest unweighted path. Their calculation or parsing conventions apply to the corresponding result fields.2, 3
| Input field | Meaning and units | Accepted input |
|---|---|---|
| words | Words | Required. Array of Text; minimum UTF-16 length 1; maximum UTF-16 length 16.; minimum items 2; maximum items 64. |
| minimumSteps | Minimum Steps | Required. Safe integer; minimum 1; maximum 63. |
| provenance | Provenance | Required. Text; minimum UTF-16 length 1; maximum UTF-16 length 512. |
| seed | Optional numeric seed; takes precedence over context randomness. Without either, use the fixed tool.io default seed. | Optional. Safe integer. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| puzzle | Puzzle | Required. Object; no unknown keys. |
| puzzle.start | Start | Required. Text; minimum UTF-16 length 1; maximum UTF-16 length 16. |
| puzzle.target | Target | Required. Text; minimum UTF-16 length 1; maximum UTF-16 length 16. |
| answer | Answer | Required. Object; no unknown keys. |
| answer.shortestPath | Shortest Path | Required. Array of Text; minimum UTF-16 length 1; maximum UTF-16 length 16.; minimum items 2; maximum items 64. |
| answer.steps | Steps | Required. Safe integer. |
| edges | Edges | Required. Array of Array of Text; minimum UTF-16 length 1; maximum UTF-16 length 16.; minimum items 2; maximum items 2.; minimum items 0; maximum items 2016. |
| eligiblePairCount | Eligible Pair Count | Required. Safe integer. |
| provenance | Provenance | Required. Text; minimum UTF-16 length 1; maximum UTF-16 length 512. |
| randomness | Replay metadata: source is seed or context; seed is the normalized 32-bit seed or null for a context source. | Required. Object; no unknown keys. |
| randomness.seed | Optional numeric replay seed; normalization and precedence are explained below. | Required. Safe integer. or Null. |
| randomness.source | Source | Required. Text; one of "context", "seed". |
An explicit safe-integer seed takes precedence over injected context randomness and is normalized to an unsigned 32-bit integer. With no seed and no context source, replay uses the fixed tool.io default seed. A context source must return finite values from zero inclusive to one exclusive; its advancing state must be retained separately. randomness records the source and normalized seed, or null for context. These generators are not cryptographic random sources.
{
"input": {
"words": [
"cat",
"cot",
"cog",
"dog"
],
"minimumSteps": 2,
"provenance": "Caller-supplied illustrative word bank",
"seed": 42
},
"output": {
"puzzle": {
"start": "cat",
"target": "dog"
},
"answer": {
"shortestPath": [
"cat",
"cot",
"cog",
"dog"
],
"steps": 3
},
"edges": [
[
"cat",
"cot"
],
[
"cog",
"cot"
],
[
"cog",
"dog"
]
],
"eligiblePairCount": 3,
"provenance": "Caller-supplied illustrative word bank",
"randomness": {
"seed": 42,
"source": "seed"
}
}
}Limitations and assumptions
- The supplied lexicon defines all legal words. An empty eligible-pair bank is an error. The returned ladder is one shortest answer and can have equally short alternatives.
- A replay requires the same complete input and implementation. Randomized construction does not guarantee uniform coverage of every feasible output; finite samples can repeat unless a distinct-selection rule is explicitly stated.
- The field tables state structural bounds; cross-field constraints and bounded search or output budgets also apply. Unknown keys are rejected where the object contract disallows them. Input errors are distinct from null fields and deliberate invalid controls in a successful output.
Alternative or Complementary methods
For a supplied example, inspect the returned construction or delegated check directly. To evaluate a consumer, also test cases chosen for its own boundaries; a generated finite corpus does not establish exhaustive coverage.
References
Similar or alternative tools
- Random Sorting Inversion Challenge Generator
Construct a permutation with an exact sampled feasible inversion count using sequential constrained Lehmer digits and retain its sorted answer; sampling is not uniform over permutations.
- Random Word Search Puzzle Generator
Place caller-supplied ASCII words in a seeded bounded grid using selected compass directions, compatible crossings, and backtracking, then fill unused cells with random uppercase letters; return planted placements and a separate answer grid, without a unique-solution or no-accidental-word guarantee.