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Filtering large numbers

In many applications, filtering data is an essential step in processing large datasets. For example, in financial applications, age-restricted platforms, or performance tracking systems, you may need to remove values above a certain threshold. In this exercise, you will practice using an Iterator to traverse a collection and remove numbers greater than 25, ensuring it has only relevant values.

All the necessary classes from java.util have been imported for you.

この演習はコースの一部です

Input/Output and Streams in Java

コースを見る

演習の手順

  • Create an Iterator for the created set numbers.
  • Use a while loop to check if the set numbers has more elements.
  • Retrieve the next element and assign to a new variable current.
  • If the number is greater than 25, remove it.

実践的なインタラクティブ演習

このサンプルコードを完成させて、この演習に挑戦してみましょう。

public class NumberFilter {
    public static void main(String[] args) {
        HashSet numbers = new HashSet<>();

        numbers.add(10);
        numbers.add(20);
        numbers.add(30);
        numbers.add(40);
        numbers.add(50);

        // Create a new Iterator object
        Iterator it = numbers.____();
        
        // Check if more elements exist
        while (it.____()) {
        	// Retrieve next element
        	int current = it.____();
            if (current > 25) {
            	// Remove the retrieved element
                it.____();
            }
        }

        System.out.println(numbers);
    }
}
コードを編集して実行