minOrNull, maxOrNull

minOrNull and maxOrNull functions return the smallest and the largest element of a collection. If the collection is empty, they return null.

fun main() {

    val numbers = listOf(1, 2, 3)
    val empty = emptyList<Int>()
    val only = listOf(3)

    println("Numbers: $numbers, min = ${numbers.minOrNull()} max = ${numbers.maxOrNull()}") // 1
    println("Empty: $empty, min = ${empty.minOrNull()}, max = ${empty.maxOrNull()}")        // 2
    println("Only: $only, min = ${only.minOrNull()}, max = ${only.maxOrNull()}")            // 3
}

1. For non-empty collection, functions return the smallest and the largest element.
2. For empty collections, both functions return null.
3. For collection with only one element, both functions return the same value.