Testdome Java Questions And Answers |link| Jun 2026

import java.util.HashMap; import java.util.Map; public class TwoSum public static int[] findTwoSum(int[] list, int target) public static void main(String[] args) int[] indices = findTwoSum(new int[] 3, 1, 5, 7, 5, 9 , 10); if(indices != null) System.out.println(indices[0] + " " + indices[1]); Use code with caution. Key Logic Breakdown: A nested loop yields

Follow this structured approach when solving problems inside the TestDome window:

public class TwoSum public static int[] findTwoSum(int[] list, int sum) for (int i = 0; i < list.length; i++) for (int j = i + 1; j < list.length; j++) if (list[i] + list[j] == sum) return new int[] i, j ; return null; Use code with caution. testdome java questions and answers

class Node public int value; public Node left, right; public Node(int value, Node left, Node right) this.value = value; this.left = left; this.right = right; public class BinarySearchTree public static boolean contains(Node root, int value) Node current = root; while (current != null) if (current.value == value) return true; else if (value < current.value) current = current.left; else current = current.right; return false; public static void main(String[] args) Node n1 = new Node(1, null, null); Node n3 = new Node(3, null, null); Node n2 = new Node(2, n1, n3); System.out.println(contains(n2, 3)); // Expected output: true Use code with caution.

import java.util.HashMap; import java.util.Map; public class TwoSum public static int[] findTwoSum(int[] list, int target) list.length < 2) return null; // Map to store: Value -> Index Map map = new HashMap<>(); for (int i = 0; i < list.length; i++) int complement = target - list[i]; if (map.containsKey(complement)) return new int[] map.get(complement), i ; map.put(list[i], i); return null; public static void main(String[] args) int[] indices = findTwoSum(new int[] 3, 1, 5, 7, 5, 9 , 10); if(indices != null) System.out.println(indices[0] + " " + indices[1]); Use code with caution. import java

Implement a method that checks if a username is valid. A valid username:

: Identifying and correcting logic errors or performance issues in existing code snippets. Refactoring & OOP Design Refactoring & OOP Design import java

import java.io.*;

"Check if a string is a palindrome without using built-in reverse functions." Alex’s mind raced back to late-night sessions on DigitalOcean Two pointers, Alex thought. One at the start, one at the end. Compare and move inward. As the timer ticked down, a question about Object-Oriented Programming (OOP)