list
val lists = listOf<String>("AAA", "BBB", "CCC", "DDD");
println(lists.count()); // 4
for ((i,e) in lists.withIndex()){
println("$i -> $e"); // 0 -> AAA 1 -> BBB 2 -> CCC 3 -> DDD
}
map
import java.util.TreeMap
val map = TreeMap<String, String>();
map["A"] = "AAA";
map["B"] = "BBB";
map["C"] = "CCC";
map["D"] = "DDD";
println(map.count()); // 4
for ((i,e) in map){
println("$i -> $e"); // A -> AAA B -> BBB C -> CCC D -> DDD
}
函数表达式
val add = {x:Int, y: Int -> x+y}
println(add(1, 2)); // 3
n的阶乘
fun funA(n: Int): Int {
return if (n == 1 || n == 0) 1 else n * funA(n - 1);
}
println(funA(3)); // 6
