Java TreeSet size()用法及代码示例

// Java code to illustrate size() 
import java.util.*; 
import java.util.TreeSet; 
  
public class TreeSetDemo { 
    public static void main(String args[]) 
    { 
        // Creating an empty TreeSet 
        TreeSet<String> tree = new TreeSet<String>(); 
  
        // Use add() method to add elements into the Set 
        tree.add("Welcome"); 
        tree.add("To"); 
        tree.add("Geeks"); 
        tree.add("4"); 
        tree.add("Geeks"); 
        tree.add("TreeSet"); 
  
        // Displaying the TreeSet 
        System.out.println("TreeSet: " + tree); 
  
        // Displaying the size of the set 
        System.out.println("The size of the set is: " + tree.size()); 
    } 
}