Single Number II
Explore how to find two elements that appear only once in an array where all other elements appear twice. Learn to apply bitwise manipulation efficiently using constant extra space, enhancing problem-solving skills for this coding interview pattern.
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Statement
Given a non-empty array arr, in which exactly two elements appear once, and all the other elements appear twice, return the two elements that appeared only once.
Note: The result can be returned in any order. The solution should use only constant extra space.
Constraints:
arr.lengtharr[i]
Examples
Understand the problem
Let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:
Two Single Numbers
(Select all that apply.) What is the output if the following array is given as an input?
arr = [1, 6, 2, 1, 2, 4, 7, 4] Multi-select
[6, 2]
[6, 7]
[7, 6]
[1, 2, 4]
Figure it out!
We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.
Try it yourself
Implement your solution in the following coding playground:
import java.util.*;public class TwoSingleNumbers{public static int[] twoSingleNumbers(int[] arr) {// Replace this placeholder return statement with your codereturn new int[]{};}}