How to get all the keys from a Scala map

In order to get all the keys from a Scala map, we need to use either keySet method (to get all the keys as a set) or we can use keys method and if you want to get the keys as an iterator, you need to use keysIterator method. Now, lets check some examples.
Example #1:

// Scala program of keySet()
// method

// Creating object
object GfG
{

    // Main method
    def main(args:Array[String])
    {

        // Creating a map
        val m1 = Map(3 -> "geeks", 4 -> "for", 2 -> "cs")

        // Applying keySet method
        val result = m1.keySet

        // Displays output
        println(result)

    }
}

Output:

Set(3, 4, 2)

Here, keySet method is utilized.
Example #2:

// Scala program of keys()
// method

// Creating object
object GfG
{

    // Main method
    def main(args:Array[String])
    {

        // Creating a map
        val m1 = Map(3 -> "geeks", 4 -> "for", 2 -> "cs")

        // Applying keys method
        val result = m1.keys

        // Displays output
        println(result)

    }
}

Output:

Set(3, 4, 2)

Here, keys method is utilized.
Example #3:

// Scala program of keysIterator()
// method

// Creating object
object GfG
{

    // Main method
    def main(args:Array[String])
    {

        // Creating a map
        val m1 = Map(3 -> "geeks", 4 -> "for", 2 -> "cs")

        // Applying keysIterator method
        val result = m1.keysIterator

        // Displays output
        println(result)

    }
}

Output:

non-empty iterator

Here, keysIterator method is utilized.