New update is available. Click here to update.

Solve problems & track your progress

Checkout your overall progress in every topic here

Become

Sensei

in DSA topics

Open the topic and solve more problems associated with it to improve your skills

Check out the skill meter for every topic

See how many problems you are left with to solve for cracking any stage. Score more than zero to get your progress counted.

Problem

Submissions

Find Unique

Easy

0/40

539 upvotes

Problem Statement

You have been given an integer array/list(ARR) of size N. Where N is equal to [2M + 1].

Now, in the given array/list, 'M' numbers are present twice and one number is present only once.

You need to find and return that number which is unique in the array/list.

Note:

Unique element is always present in the array/list according to the given condition.

Detailed explanation ( Input/output format, Notes, Images )

Input format :

The first line contains an Integer 't' which denotes the number of test cases or queries to be run. Then the test cases follow.

First line of each test case or query contains an integer 'N' representing the size of the array/list.

Second line contains 'N' single space separated integers representing the elements in the array/list.

Output Format :

For each test case, print the unique element present in the array.

Output for every test case will be printed in a separate line.

Constraints :

1 <= t <= 10^2
0 <= N <= 10^3
Time Limit: 1 sec

Sample Input 1:

1
7
2 3 1 6 3 6 2

Sample Output 1:

Sample Input 2:

2
5
2 4 7 2 7
9
1 3 1 3 6 6 7 10 7

Sample Output 2:

4
10

Auto

Console