RosettaCodeData/Task/Power-set/Kotlin/power-set.kotlin
2017-09-25 22:28:19 +02:00

38 lines
872 B
Text

// version 1.1.3
class PowerSet<T>(val items: List<T>) {
private lateinit var combination: IntArray
init {
println("Power set of $items comprises:")
for (m in 0..items.size) {
combination = IntArray(m)
generate(0, m)
}
}
private fun generate(k: Int, m: Int) {
if (k >= m) {
println(combination.map { items[it] })
}
else {
for (j in 0 until items.size)
if (k == 0 || j > combination[k - 1]) {
combination[k] = j
generate(k + 1, m)
}
}
}
}
fun main(args: Array<String>) {
val itemsList = listOf(
listOf(1, 2, 3, 4),
emptyList<Int>(),
listOf(emptyList<Int>())
)
for (items in itemsList) {
PowerSet(items)
println()
}
}