Scala - collections in Scala

Category : Scala | Sub Category : Scala Programs | By Prasad Bonam Last updated: 2023-10-01 08:14:49 Viewed : 265

Scala provides a rich set of collection libraries that offer a wide range of data structures and methods for working with collections. Here are some common examples using collections in Scala:

1. Lists:

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// Creating a List
val myList = List(1, 2, 3, 4, 5)

// Accessing elements
val firstElement = myList.head // 1
val restOfTheList = myList.tail // List(2, 3, 4, 5)

// Adding elements
val newList = myList :+ 6 // List(1, 2, 3, 4, 5, 6)

// Mapping elements
val doubledList = myList.map(_ * 2) // List(2, 4, 6, 8, 10)

2. Sets:

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// Creating a Set
val mySet = Set(1, 2, 3, 4, 5)

// Checking for element existence
val containsThree = mySet.contains(3) // true

// Adding elements
val newSet = mySet + 6 // Set(1, 2, 3, 4, 5, 6)

// Intersection of sets
val otherSet = Set(4, 5, 6, 7, 8)
val intersection = mySet.intersect(otherSet) // Set(4, 5, 6)

3. Maps:

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// Creating a Map
val myMap = Map("Alice" -> 25, "Bob" -> 30, "Charlie" -> 22)

// Accessing values
val aliceAge = myMap("Alice") // 25

// Adding key-value pairs
val newMap = myMap + ("David" -> 28)

// Iterating through key-value pairs
myMap.foreach { case (name, age) =>
  println(s"$name is $age years old")
}

4. Sequences:

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// Creating a Sequence
val mySeq = Seq(1, 2, 3, 4, 5)

// Concatenating sequences
val combinedSeq = mySeq ++ Seq(6, 7, 8)

// Filtering elements
val evenNumbers = mySeq.filter(_ % 2 == 0) // Seq(2, 4)

5. Arrays:

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// Creating an Array
val myArray = Array(1, 2, 3, 4, 5)

// Accessing elements
val thirdElement = myArray(2) // 3

// Updating elements
myArray(0) = 10

// Converting to List
val myList = myArray.toList

These examples cover some of the fundamental operations you can perform on collections in Scala. Scalas collections library is extensive and versatile, offering many more data structures and methods for various use cases.