Scala 不可变 TreeSet count() 方法

在 Scala 不可变TreeSet class中， count()方法用于计算 TreeSet 中满足给定谓词的元素的数量。

Method Definition: def count(p: (A) => Boolean): Int

Return Type: It returns the count the number of elements in the TreeSet that satisfies a given predicate.

示例 #1：

// Scala program of count() 
// method 
  
// Import TreeSet
import scala.collection.immutable._
  
// Creating object 
object GfG 
{ 
  
    // Main method 
    def main(args:Array[String]) 
    { 
      
        // Creating TreeSet
        val t1 = TreeSet(2, 1, 3, 4, 5) 
          
        // Print the TreeSet
        println(t1) 
          
        // Applying count() method  
        val result = t1.count(x => {x % 2 == 0})
          
        // Display output 
        print("Number of even element in the TreeSet: " + result) 
           
    } 
} 

输出：

TreeSet(1, 2, 3, 4, 5)
Number of even element in the TreeSet: 2

示例 #2：

// Scala program of count() 
// method 
  
// Import TreeSet
import scala.collection.immutable._
  
// Creating object 
object GfG 
{ 
  
    // Main method 
    def main(args:Array[String]) 
    { 
      
        // Creating TreeSet
        val t1 = TreeSet(2, 1, 3, 4, 5) 
          
        // Print the TreeSet
        println(t1) 
          
        // Applying count() method  
        val result = t1.count(x => {x % 2 != 0})
          
        // Display output 
        print("Number of odd element in the TreeSet: " + result) 
           
    } 
} 

输出：

TreeSet(1, 2, 3, 4, 5)
Number of odd element in the TreeSet: 3