Scala Stack filter() 方法示例

在 Scala Stack class中， filter()方法用于返回一个新堆栈，该堆栈由满足给定谓词的所有元素组成。

Method Definition: def filter(pred: (A) => Boolean): Stack[A]

Return Type: It returns a new stack that consists of all the elements that satisfy a given predicate.

示例 #1：

// Scala program of filter() 
// method 
  
// Import Stack 
import scala.collection.mutable._
  
// Creating object 
object GfG 
{ 
  
    // Main method 
    def main(args:Array[String]) 
    { 
      
        // Creating stack  
        val s1 = Stack(1, 3, 2, 7, 6, 5)  
          
        // Print the stack
        println(s1)
            
        // Applying filter method  
        val result = s1.filter(x => {x % 2 == 1}) 
          
        // Display output
        println("Odd elements: " + result)
    } 
} 

输出：

Stack(1, 3, 2, 7, 6, 5)
Odd elements: Stack(1, 3, 7, 5)

示例 #2：

// Scala program of filter() 
// method 
  
// Import Stack 
import scala.collection.mutable._
  
// Creating object 
object GfG 
{ 
  
    // Main method 
    def main(args:Array[String]) 
    { 
      
        // Creating stack  
        val s1 = Stack(1, 3, 2, 7, 6, 5)  
          
        // Print the stack
        println(s1)
            
        // Applying filter method  
        val result = s1.filter(x => {x % 3 == 0}) 
          
        // Display output
        println("Elements divisible by 3: " + result)
    } 
} 

输出：

Stack(1, 3, 2, 7, 6, 5)
Elements divisible by 3: Stack(3, 6)