Scala | Value Classes

Scala sum Map values

Last Updated : 26 Jul, 2019

In Scala, the sum of the map elements can be done by utilizing foldLeft method.

Syntax : m1.foldLeft(0)(_+_._1)

Here, m1 is used for a Map, foldLeft is a method that takes an initial value zero. it will take previous result and add it to the next map key value.

Return Type: It returns the sum of all the elements of the map.

Example #1:

// Scala program of sum() 
// method 
  
// Creating object 
object GfG 
{  
  
    // Main method 
    def main(args:Array[String]) 
    { 
      
        // Creating a map 
        val m1 = Map(3 -> "geeks", 1 -> "for", 2 -> "cs") 
          
        // Applying sum method 
        val result = m1.foldLeft(0)(_+_._1) 
          
        // Displays output 
        println(result) 
      
    } 
} 

Output:

Here, zero in the foldLeft method is the initial value.
Example #2:

// Scala program of sum() 
// method 
  
// Creating object 
object GfG 
{  
  
    // Main method 
    def main(args:Array[String]) 
    { 
      
        // Creating a map 
        val m1 = Map(3 -> "geeks", 1 -> "for", 1 -> "for") 
          
        // Applying sum method 
        val result = m1.foldLeft(0)(_+_._1) 
          
        // Displays output 
        println(result) 
      
    } 
} 

Output:

Scala | Value Classes

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