Java Program to Find the kth Element in an Array

In this post, you will learn how to find the kth element in an array using the Java programming language.

import java.util.Arrays;
import java.util.Scanner;

public class KthElementFinder {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        
        // Input: Size of the array
        System.out.print("Enter the size of the array: ");
        int n = scanner.nextInt();
        
        // Input: Array elements
        int[] array = new int[n];
        System.out.println("Enter the elements of the array: ");
        for (int i = 0; i < n; i++) {
            array[i] = scanner.nextInt();
        }
        
        // Input: Position k
        System.out.print("Enter the value of k: ");
        int k = scanner.nextInt();
        
        if (k > 0 && k <= n) {
            // Sort the array (if you want the kth smallest or largest)
            Arrays.sort(array);
            
            // Output: kth element in the sorted array
            System.out.println("The " + k + "th element in the array is: " + array[k - 1]);
        } else {
            System.out.println("Invalid value of k.");
        }
        
        scanner.close();
    }
}

Enter the size of the array: 6
Enter the elements of the array: 
89 82 58 19 63 50
Enter the value of k: 4
The 4th element in the array is: 63

Code Explanation:

1. Input the Array: The program first prompts the user to input the size of the array and then the elements of the array.

2. Input k: It then asks for the position k (1-based index) of the element you want to find.

3. Sort the Array: The program sorts the array. (This step is necessary if you want to find the kth smallest or kth largest element.)

4. Retrieve the kth Element: The program retrieves and prints the kth element from the sorted array.

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