Question

How to use a list as a stack in Scala

Answer 1

object FunctionalStack extends App {
  var stack: List[String] = List()

  // Push elements 
  stack = "Scala" :: stack
  stack = "C" :: stack
  stack = "C++" :: stack
  stack = "Java" :: stack
  stack = "Python" :: stack

  // Peek
  println(s"Top of stack: ${stack.head}\n")

   // Print the stack
  println("Current stack:")
  stack.foreach(println)
  println()

  // Pop
  while (stack.nonEmpty) {
    println(stack.head)
    stack = stack.tail
  }
  println()

  // Print the stack
  println("Current stack:")
  stack.foreach(println)
}


 
 
/*
run:
  
Top of stack: Python

Current stack:
Python
Java
C++
C
Scala

Python
Java
C++
C
Scala

Current stack:
  
*/

 

 

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