Building on the success and enthusiasm of previous years, we’re excited to bring you a fresh selection of algorithms to explore and implement this December!
Each Day, Each Algorithm ;) Finish them all to get a certificate :)
Send a pull request only after completing all 31 algorithms.
Please submit all PRs on or before January 21st 11:59 PM IST.
We have a small collection of algorithms, one for every day of the month. Scroll down to take a look at them.
All you need to do is fork this repository, implement all 31 algorithms and send a pull request over to us.
Check out our FAQ for more information.
- December 01 - The Vanishing Number
- December 02 - The Wave Sort Challenge
- December 03 - Alternating Square Arrangement
- FAQ
Imagine a race event with N participants, each having a unique bib number from 1 to N.
After the race, the event organizers collect the bib numbers of all participants who showed
up. However, one participant didn’t show up, and their bib number is missing. The task is to
find out which bib number is missing in order to identify the participant who was absent.
Given an integer N and an array of size N-1 containing N-1 numbers between 1 to N. Find
the number(between 1 to N), that is not present in the given array.
Example 1:
Input Format:
N = 5, array[] = {1,2,4,5}
Result: 3
Explanation:
In the given array, number 3 is missing. So, 3 is the answer.
Example 2:
Input Format:
N = 3, array[] = {1,3}
Result: 2
Imagine you're at a music concert, surrounded by thousands of fans.
As the music plays, the crowd begins to move in a rhythmic pattern, rising and falling like a wave.
The energy is contagious, and everyone follows the same wave-like motion.
Now, think of the crowd as an unsorted array of integers, and your job is to arrange them in such a way that
the heights of the fans rise and fall, just like the waves at the concert.
Your task is to organize the array in a similar wave-like fashion!
Sort an array in wave form
Given an unsorted array of integers, sort the array into a wave array. An array arr[0..n-1] is sorted in wave form if:
arr[0] >= arr[1] <= arr[2] >= arr[3] <= arr[4] >= ….
Example 1:
Input:
arr[] = {10, 5, 6, 3, 2, 20, 100, 80}
Output:
arr[] = {10, 5, 6, 2, 20, 3, 100, 80}
Explanation:
Here you can see {10, 5, 6, 2, 20, 3, 100, 80}. The first element is larger than the second, and the same pattern repeats again.
Large element – small element – large element – small element, and so on.
It can also be in the opposite pattern (small element – large element – small element – large element).
All you need to maintain is the up-down fashion, which represents a wave. There can be multiple answers.
Example 2:
Additional Scenario
Input:
arr[] = {1, 2, 3, 4, 5, 6}
Output:
arr[] = {2, 1, 4, 3, 6, 5}
Explanation:
In this case, we swap adjacent elements to form a wave-like array.
{2, 1, 4, 3, 6, 5} satisfies the condition where elements are alternately large and small.
You are given integers  (number of red squares) and  (number of blue squares).
Your task is to arrange the squares in a sequence such that:
No two adjacent squares have the same color.
If it is not possible to create such an arrangement, return "Not possible".
Input
Two integers:
R: Number of red squares.
B: Number of blue squares.
Output
A valid arrangement as a string (e.g., "RBRBR" or "BRBRB") that satisfies the condition, or "Not possible" if no valid arrangement exists.
Sample Input and Output: Example 1:
Input:
R = 3
B = 2
Output:
"RBRBR"
Explanation:
The sequence "RBRBR" satisfies the condition since no two adjacent squares are the same color.
Example 2:
Input:
R = 4
B = 2
Output:
"Not possible"
Explanation:
It is impossible to arrange 4 red squares and 2 blue squares without
having two adjacent squares of the same color. Hence, the output is "Not possible".
Anyone who is passionate about coding and can dedicate a little time a day for the challenge for the next 31 days.
You don't need to submit it everyday. Just submit it once you're done with all 31 algorithms.
Not a problem. While coding every day is nice, we understand that other commitments might interfere with it.
Plus its holiday season. So you don't have to solve one problem every day.
Go at your own pace. One per day or 7 a week or even all 30 in a day.
Anything! New to GoLang? Best way to practice it.
Wanna find out what all this hype about Python is? Use it!
Any and all languages are welcome.
Maybe you could try using a different language for every problem as a mini-challenge?
If you are new to Git or GitHub, check out this out GitHub
Our code ninjas are hard at work preparing the rest of the problems. Don't worry, they'll be up soon.
We have a folder for each day of the month. Simply complete your code and move the file into that folder.
Be sure to rename your file to the following format: language_username or language_username_problemname
Some examples:
python3_exampleUser.py
c_exampleUser.c
Please do not modify any existing files in the repository.
I forked the repository but some problems were added only after that. How do I access those problems?
Not to worry! Open your nearest terminal or command prompt and navigate over to your forked repository.
Enter these commands:
git remote add upstream https://github.com/SVCE-ACM/A-December-of-Algorithms-2024.git
git fetch upstream
git merge upstream/mainIf you're curious, the commands simply add a new remote called upstream that is linked to this repository. Then it 'fetches' or retrieves the contents of the repository and attempts to merge it with your progress. Note that if you've already added the upstream repository, you don't need to re-add it in the future while fetching the newer questions.
This shouldn't happen unless you modify an existing file in the repository. There's a lot of potential troubleshooting that might be needed, but the simplest thing to do is to make a copy of your code outside the repository and then clone it once again. Now repeat the steps from the answer above. Merge it and then add your code. Now proceed as usual. :)
Open up an issue on this repository and we'll do our best to help you out.
