test.kt

test.kt

        fun main(args: Array<String>) {

            val markets = listOf(
                    OD("ABQ","PHX"),
                    OD("DAL", "HOU"),
                    OD("HOU", "PHX")
            )

            val distinctStations = markets.asSequence()
                    .flatMap { sequenceOf(it.orig, it.dest) }
                    .distinct()
                    .toList()

            println(distinctStations)
        }

        data class OD(val orig: String, val dest: String)