Smallest and Biggest in One Pass (teeing)

Collectors.teeing was added in Java 12.

/*
 * Problem : Process an array.
 * Input   : n, then n integers.
 * Output  : The smallest and the biggest value.
 * Approach: Collectors.teeing.
 * Time    : O(n)
 * Space   : O(n)
 * Java    : 12 or newer.
 */
import java.util.Scanner;

public class Main {
    // This method solves the task. It receives the input and returns the answer.
    static String solve(int[] a) {
        // Step 1: A stream can be read only once. Collectors.teeing (Java 12) sends every value to two collectors at the same time
        // and joins their two results with a function.
        return java.util.Arrays.stream(a).boxed().collect(java.util.stream.Collectors.teeing(
                java.util.stream.Collectors.minBy(Integer::compare),
                java.util.stream.Collectors.maxBy(Integer::compare),
                (smallest, biggest) -> smallest.get() + " " + biggest.get()));
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int size = scanner.nextInt();
        int[] a = new int[size];
        for (int i = 0; i < size; i++) {
            a[i] = scanner.nextInt();
        }
        System.out.println(solve(a));
    }
}