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AI Features

Single Number

Understand how to find the single unique number in an array where every other element appears twice. Learn bitwise manipulation techniques in C++ to solve the problem efficiently with linear time complexity and constant space.

Statement

Given an array of integers, where every element appears twice except for one, find the element that occurs only once.

Note: The solution must have linear runtime and constant space complexity.

Constraints:

  • 11 \leq nums.length 103\leq 10^3
  • 3×103-3 \times 10^3 \leq nums[i] 3×103\leq 3 \times 10^3

Example

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:

Single Number

1.

From the given array of integers, find the number that appears once.

array = [1, 2, 4, 1, 2, 4, 9, 6, 7, 6, 7]

A.

1

B.

2

C.

9

D.

6


1 / 2

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.

Sequence - Vertical
Drag and drop the cards to rearrange them in the correct sequence.

1
2
3
4
5

Try it yourself

Implement your solution in the following coding playground:

C++
usercode > main.cpp
#include <iostream>
#include<vector>
int SingleNumber(vector<int> nums)
{
// Replace this placeholder return statement with your code
return -1;
}
Single Number