문자열의 모든 순열찾기

fun getPermutations(s: String): List<String> {
    if (s.length <= 1) return listOf(s)
    val permutations = mutableListOf<String>()
    for (i in s.indices) {
        for (perm in getPermutations(s.removeRange(i, i + 1))) {
            permutations.add(s[i] + perm)
        }
    }
    return permutations
}

fun main() {
    println(getPermutations("abc")) // [abc, acb, bac, bca, cab, cba]
}