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maxBy

Platform and version requirements: JVM (1.0), JS (1.0), Native (1.0)
inline fun <T, R : Comparable<R>> Array<out T>.maxBy(
    selector: (T) -> R
): T?
inline fun <R : Comparable<R>> ByteArray.maxBy(
    selector: (Byte) -> R
): Byte?
inline fun <R : Comparable<R>> ShortArray.maxBy(
    selector: (Short) -> R
): Short?
inline fun <R : Comparable<R>> IntArray.maxBy(
    selector: (Int) -> R
): Int?
inline fun <R : Comparable<R>> LongArray.maxBy(
    selector: (Long) -> R
): Long?
inline fun <R : Comparable<R>> FloatArray.maxBy(
    selector: (Float) -> R
): Float?
inline fun <R : Comparable<R>> DoubleArray.maxBy(
    selector: (Double) -> R
): Double?
inline fun <R : Comparable<R>> BooleanArray.maxBy(
    selector: (Boolean) -> R
): Boolean?
inline fun <R : Comparable<R>> CharArray.maxBy(
    selector: (Char) -> R
): Char?
inline fun <T, R : Comparable<R>> Iterable<T>.maxBy(
    selector: (T) -> R
): T?
@ExperimentalUnsignedTypes inline fun <R : Comparable<R>> UIntArray.maxBy(
    selector: (UInt) -> R
): UInt?
@ExperimentalUnsignedTypes inline fun <R : Comparable<R>> ULongArray.maxBy(
    selector: (ULong) -> R
): ULong?
@ExperimentalUnsignedTypes inline fun <R : Comparable<R>> UByteArray.maxBy(
    selector: (UByte) -> R
): UByte?
@ExperimentalUnsignedTypes inline fun <R : Comparable<R>> UShortArray.maxBy(
    selector: (UShort) -> R
): UShort?

Returns the first element yielding the largest value of the given function or null if there are no elements.

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val nameToAge = listOf("Alice" to 42, "Bob" to 28, "Carol" to 51)
val oldestPerson = nameToAge.maxBy { it.second }
println(oldestPerson) // (Carol, 51)

val emptyList = emptyList<Pair<String, Int>>()
val emptyMax = emptyList.maxBy { it.second }
println(emptyMax) // null
//sampleEnd
}
Platform and version requirements: JVM (1.0), JS (1.0), Native (1.0)
inline fun <K, V, R : Comparable<R>> Map<out K, V>.maxBy(
    selector: (Entry<K, V>) -> R
): Entry<K, V>?

Returns the first entry yielding the largest value of the given function or null if there are no entries.

import kotlin.test.*

fun main(args: Array<String>) {
//sampleStart
val nameToAge = listOf("Alice" to 42, "Bob" to 28, "Carol" to 51)
val oldestPerson = nameToAge.maxBy { it.second }
println(oldestPerson) // (Carol, 51)

val emptyList = emptyList<Pair<String, Int>>()
val emptyMax = emptyList.maxBy { it.second }
println(emptyMax) // null
//sampleEnd
}

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Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/max-by.html