[Kotlin] Reverse a List with downTo

fun reverse(numbers: List<Int>): List<Int> {
    var res = arrayListOf<Int>()
    for (i in 0..numbers.size-1) {
        res.add(numbers.get(numbers.size - 1 - i))
    }
    return res
}

fun reverse2(numbers: List<Int>): List<Int> {
    var res = arrayListOf<Int>()
    for (i in numbers.size - 1 downTo 0) {
        res.add(numbers.get(i))
    }
    return res
}

fun main() {
    val numbers = listOf(1,2,4,6,7,8)
    val res = reverse(numbers)
    val res2 = reverse2(numbers)
    println(res) // [8, 7, 6, 4, 2, 1]
    println(res2) // [8, 7, 6, 4, 2, 1]
}
原文地址:https://www.cnblogs.com/Answer1215/p/13799089.html