RandomWordGenerator.kt

import kotlin.random.Random

class RandomWordGenerator(words: List<String>) {
    private val graph = mutableMapOf<Char, MutableSet<Char>>()
    private val firstLetters = mutableSetOf<Char>()
    private val lastLetters = mutableSetOf<Char>()

    init {
        words.forEach { word ->
            word.forEachIndexed { index, currentLetter ->
                if (currentLetter !in graph) graph[currentLetter] = mutableSetOf()

                val nextLetter = if (index < word.lastIndex) word[index + 1] else null
                if (nextLetter != null) graph[currentLetter]?.add(nextLetter)
            }

            firstLetters.add(word.first())
            lastLetters.add(word.last())
        }
    }

    fun generateRandomWord(): String {
        val randomWord = StringBuilder()

        var currentLetter = firstLetters.random()
        while (true) {
            randomWord.append(currentLetter)

            val nextLetter = graph[currentLetter]?.randomOrNull() ?: return randomWord.toString()
            if (nextLetter in lastLetters && Random.nextBoolean() && Random.nextBoolean()) {
                randomWord.append(nextLetter)
                return randomWord.toString()
            } else {
                currentLetter = nextLetter
            }
        }
    }
}

fun main() {
    val words = listOf("apple", "banana", "cabbage")
    val generator = RandomWordGenerator(words)

    val randomWord = generator.generateRandomWord()
    println(randomWord)
}