import scala.collection.mutable
 
object Main extends App {
val m1 = Map("A" -> 1, "B" -> 2, "C" -> 3)
println(m1)
m1.updated("B", 4)
println(m1)
 
val m2 = mutable.Map("A" -> 1, "B" -> 2, "C" -> 3)
println(m2)
m2("B") = 5
println(m2)
}