kotlin Listの要素をグループ化してカウントする方法
環境
Windows10 Home 64bit
Java 19.0.1
Kotlin 1.7.20-release-201
構文
リスト名.groupingBy({ 条件 }.eachCount())
「groupingBy」関数を使って、Listの要素をグループ化してカウントします。
使用例
fun main() {
val listLan = listOf("stuydy","skill","become","smart","arkgame")
println(listLan.groupingBy { it.length }.eachCount())
println(listLan)
}
fun main() {
val listLan = listOf("stuydy","skill","become","smart","arkgame")
println(listLan.groupingBy { it.length }.eachCount())
println(listLan)
}
fun main() {
val listLan = listOf("stuydy","skill","become","smart","arkgame")
println(listLan.groupingBy { it.length }.eachCount())
println(listLan)
}
実行結果
{6=2, 5=2, 7=1}
[stuydy, skill, become, smart, arkgame]