Java Program: Find Second Smallest and Largest Elements in a List of Integers using Streams

Java Stream: Exercise-8 with Solution

Write a Java program to find the second smallest and largest elements in a list of integers using streams.

Sample Solution:

Java Code:

import java.util.Arrays;
import java.util.List;

public class Main {
  public static void main(String[] args) {
    List < Integer > nums = Arrays.asList(1, 17, 54, 14, 14, 33, 45, -11);
    System.out.println("List of numbers: " + nums);
    // Find the second smallest element
    Integer secondSmallest = nums.stream()
      .distinct()
      .sorted()
      .skip(1)
      .findFirst()
      .orElse(null);

    // Find the second largest element
    Integer secondLargest = nums.stream()
      .distinct()
      .sorted((a, b) -> Integer.compare(b, a))
      .skip(1)
      .findFirst()
      .orElse(null);

    System.out.println("\nSecond smallest element: " + secondSmallest);
    System.out.println("\nSecond largest element: " + secondLargest);
  }
}

Sample Output:

List of numbers: [1, 17, 54, 14, 14, 33, 45, -11]

Second smallest element: 1

Second largest element: 45

Explanation:

In the above exercise,

We create a list of integers (numbers) and use streams to find the second smallest element by applying distinct, sorting the elements in ascending order, skipping the first element, and locating the first element. Similarly, we find the second largest element by sorting the elements in descending order. The orElse method handles the case when the list is empty or there are no second smallest/largest elements.

Flowchart:

Java Code Editor:

Improve this sample solution and post your code through Disqus

Previous: Find Maximum and Minimum Values in a List of Integers using Streams.